Mange Mites-Demodex   

Localized demodectic mange

Question: Hi Dr. Mike,
We adopted our beagle mix from the Humane Society 2 months ago, when she
was 6 months old. She had a vomiting problem (which I had written you
about) which is now cleared, but now has been diagnosed with localized
demodetic mange. She has 2 tiny spots--one on her right cheek/neck and
another on her right calf. Both spots looked like little scrapes but we
decided to have them checked out to be on the safe side. Our vet did the
scrapings and confirmed mites in both places. He has placed her on
Primor 240 mg once a day and an ointment which he was out of that we
will get tomorrow. She has an app't again in 2 weeks. I have read all
that is in your archives about this mange and am worried. Our vet seems
to think it will clear up and I know you said up to 80% of localized
mange does, but I am wondering why this happened 2 months after we got
her and have given her the best of care possible after having a rocky
start (she was a starving stray) and if there is anything else we can do
at this point or if there is any type of preventative medicine or
booster to the immune system that would help in her healing and her
remaining symptom-free. She itches more than is normal, although nothing is red or oozing or infected and if you didn't look carefully for these 2 little spots, you wouldn't notice them and if you did, wouldn't think
they were anything. We really expected the vet to say she just scraped
herself playing as she seems so healthy now and playful. Is there
ANYTHING we can do to help her get better and not get an outbreak again (assuming this is going to clear up). We love this dog like a child and want her to get the best treatment available. Why is sarcoptic mange so much easier to treat and cure than this? Should Belle have any blood work done to see if anything else is wrong with her system? If I understand correctly, her immune system is not doing its job well enough and we are concerned as to the cause of this, esp. since she has had a pretty good life with us the last 2 months. She is just over 16 lbs and the vet says this is an ideal weight for her as she will remain a small beagle mix. She appears to be in good health in every other respect--her ear
infections when we got her have all cleared up (after steroid
drops--could that have triggered a suppressed immune system??) and her
vomiting stopped after she was de-wormed again (even though her tests
were negative, she must have had something). Please tell us what else we
can do to give her as good a life as possible. We are not rich by any
means, but we love her deeply and want to do everything possible.

Thank you,
Linda

Answer: Linda-

It is hard to figure out why localized demodectic mange occurs in a
particular dog. Hormonal changes as puppies age may have some effect. Local skin conditions may favor the mite, giving it a chance to reproduce
excessively until the dog's immune system is stimulated to respond.
Localized demodectic mange is a minor problem and it is not indicative of
an overall immune system deficiency. There does seem to be evidence that
controlling secondary bacterial infections is helpful so that is probably
the reason that your vet chose to use an antibiotic. The ointment most
commonly used for localized demodecosis is Goodwinol's Ointment (tm) but I think of this mostly as a placebo since localized demodecosis will clear up without any treatment in most cases. Some vets use other gels, such as benzoyl peroxide.

There is a growing trend among vets to go ahead and treat localized
demodecosis cases with amitraz (Mitaban Rx) or ivermectin (Ivomec Rx) but I really believe it is better to wait and see whether the mange will clear up on its own. I think it is better for the dog if medications do not have to
be used and it also allows an assessment of the severity of the problem and
the likelihood of a recurrence later in life. Waiting and doing nothing is
really hard for many of my clients but I truly believe it is the best
approach. Obviously, there are many vets that disagree with this assessment since treatment for localized demodecosis is fairly commonly attempted now.

It is unlikely that you will find a problem by doing blood testing in a dog
that appears to be healthy and is in her age range but there is no reason
not to check the blood chemistry and cbc values if it makes you more
comfortable.

Some dogs do absorb enough corticosteroid when eye or ear drops are used to cause some degree of immune suppression but there doesn't seem to be a strong correlation in our practice between the use of corticosteroid
containing ear medications and later occurrrences of demodectic mange. In general, this effect is slight enough that it doesn't cause problems.

I really don't know why sarcoptic mange mites are so much easier to kill
and so much more contagious. They are an entirely different species, though.

It sounds to me like you are providing a good life for Belle and that you
don't need to make any major changes right now to ensure that will continue to be the case.

Mike Richards, DVM
7/9/2000
 
 

Demodectic mange

Question: Hi Dr Mike
 

I have two dogs (mixed breeds) who stay outside our house most of the day.  1 dog, Ginger had a rawish rash at her mouth and started to limp so I took her to the vet.  They did skin scrapes and skin tests and told me that she had the beginnings of demodetic mange at the mouth and eye area, and a fungal infection in between he hind foot toenails.  I now have to apply an
amitraz solution to the mange areas once a week and I have to give her baths in Ketaconazole Shampoo (that's usually for fungal dandruff here) 2x a week.  But shes worrying at her foot and is starting to bite it raw.  What I did was clean the wound with hydrogen peroxide and betadine, and I let her wear a satellite-dishlike thing on her head so she doesn't bite or see her foot. Is there anyway to prevent itching?  I bought a "hotspot itch reliever" at the vet and its made of camomile, and tea tree oil but I am not sure if I should use it because it might make the situation worse.  Is there anything else I can ask my vet about re: the mange and the fungus? I think Kinky, my other dog - who's always with her - is starting to limp as well.

Please advise as Im worried about them and would like to prevent any further injury / pain.

Thanks. Mia
 

Answer: Mia-

How old is Ginger?  Demodectic mange in a puppy is a lot different than
demodectic mange in an older adult dog, so it would help to know which is the case.

In either case, we find that using antibiotics in dogs that itch when they
have demodectic mange is very helpful in relieving this syndrome. The
demodectic mange itself is not usually very itchy so most itchiness comes
from secondary infections. Fungal infections can itch, so that is also a
possible cause -- but our experience is that the itchiness is most often
bacterial in demodectic mange cases.

We usually use 4% chlorhexidine shampoo when we try to treat skin yeast
infections as has worked a little better for us than ketaconazole shampoo.
In some cases it is necessary to use systemic (oral) medications for the
yeast infections, though.

If there are Demodex mites in scrapings from the mouth and the feet it
would probably be better to treat the whole body by following the
directions on the package insert. If that doesn't work, there are
alternative treatments that might.

It is important not to use cortisone products in a dog with demodecosis and since these are anti-itch and available over the counter, they do sometimes get used. I know of no problems with tea tree oil or  camomile in conjunction with demodecosis, though.

There is a lot of information on the site about demodecosis but if you have
questions about it  and especially if Ginger is an older dog, please write
back.

Mike Richards, DVM
7/3/2000

Dr Mike - Ginger is 2.5 yrs old.

Answer: Mia-

 In this situation it is important to try to look for an underlying cause for the demodecosis.   Most dogs with immune system disorders that allow demodecosis to occur develop it at a younger age, usually less than one year of age. In dogs in which demodecosis occurs later, there is often something causing significant compromise of the immune system. Cushing's disease, liver disease, diabetes, high doses of prednisone or other cortisones, cancer and other strong suppressors of immune function can lead to adult onset demodecosis. It is worthwhile to put a good effort into eliminating as many of these causes as is possible through lab work and physical exam. This is a situation in which asking for referral to a veterinary dermatologist can  be a good idea, too.

I  missed the part about Kinky limping.  Demodex mites can be
spread from one dog to another but it takes an immune system deficiency for the mites to cause problems, so demodecosis is not considered to be a
contagious disease. If there is a disease or environmental problem
stressing both dogs at once it is conceivable that they might both develop
demodecosis but this is really unlikely.  On the other hand, allergies
leading to interdigital (between the toes) skin infections is a pretty
common problem in dogs and something like this could be affecting both of them, with the demodecosis being secondary to damaged skin in Ginger. There are an awful lot of causes of lameness so it is actually more likely that they have different problems, though.

Hope this helps some.

Mike Richards, DVM
7/4/2000
 
 

Demodex in toy breed - continued

  Question: I wrote to you recently about my chihuahua x toy terrier puppy with demodecis and my vet has now increased the Ivermectin to 300mcg per kilo given orally every second day and restarted the antibiotics which seems to have led to a significant improvement. Thank you. My question today is whether or not there is any way of testing for an underlying immunological problem and/or whether or not there is any way to boost her immune system. My vet was going to research whether an antiviral drug like Interferon to boost T cell production could
be helpful and I wondered whether you are aware of any research in this area.I would be fairly reluctant to try this without some good supportive evidence that it can help as I know that Interferon has a range of unpleasant side effects. My vet seems to think that there is an increasing likelihood that my pup's problems may relate to an underlying immunological problem and seems concerned about the possibility of neurotoxic problems with really long term use of Ivermectin.
Thanks, Caroline

Answer: Caroline-

I know of a number of patients treated with ivermectin for very long durations without any noticeable problems. Most of these patients are being treated daily with 225 to 300 ug/kg of ivermectin.  It may
be possible to avoid some of the adverse effects of amitraz (Mitaban Rx) by treating with yohimbine prior to dipping with amitraz but sometimes it is necessary to repeat the yohimbine to cover the whole time period when reactions occur. This might be an alternative choice if the ivermectin does seem to be causing problems at a later time. It is OK to use amitraz and ivermectin at the same time but I know that in your dog's case the amitraz seems to cause significant sedation so that can be held in reserve, too.

Humans have a lot of side effects associated with interferon use. Cats have few reported side effects from interferon use. I have only seen one study that I can remember on interferon use in dogs and there were no side effects noted in that study (it was on keratoconjunctivitis sicca, an immune
mediated eye problem where tear production is inhibited). So I would think interferon would be reasonably safe to try but would have to be a little cautious in that recommendation until I was more sure of whether dogs are going to be like people or like cats in regards to side effects.

There are tests for specific immune deficiencies but there has to be some degree of suspicion for a particular problem to make these tests practical because there are a lot of known immune deficiency disorders at this time. Before going with this approach, I would really recommend a complete lab work up, including a broad blood chemistry panel, total blood cell evaluation and perhaps X-rays of the chest and abdomen. If all of this fails to point out a problem then it might be a good idea to consider asking about referral to a veterinary immunologist or hematologist for a review of potential problems with neutrophil disorders or other immune system problems.

I haven't been too impressed with any of the medications or food additives that are supposed to stimulate the immune system, yet.  Hopefully an underlying problem can still be identified and treated.

Mike Richards, DVM
4/10/2000
 
 

Demodex treatment for toy breeds

 Question:  I am a subscriber living in NZ. I have a 4 month old Chihahua X English Toy Terrier female puppy who was diagnosed as having severe generalised Demodecis at 11weeks. She had previously been found to have Ringworm.She received Griseofulvin for 6 weeks and has been  having weekly injections of Ivomectin. She has also had a total of six weeks on antibiotics for secondary bacterial skin infections.She had a good initial response to the Ivomectin, with a brief flare up following her final vaccination,but over the past two weeks has again developed red scabby patches and hair loss over her throat and face which seem to be getting worse and spreading despite continued weekly Ivomecitin injections.In the time she has been receiving treatment she has only had a few days of looking completely clear, immediately prior to this last flare up. .
   It seems that Ivomec and Ectodex are the only treatments available here and there is a warning not to use Ectodex on Chihahuas on the bottle. What would be the dangers of using Ectodex on her? (my vet doesn't know why Chihahuas are specifically excluded from treatment). Is it likely that increasing the dose of Ivomec would be helpful? She currently receives 0.08ml but I'm not sure of the concentration.Any information or advice would be greatly appreciated
  Thank you
  Caroline

Answer: Caroline-

Ectodex (Rx) is the brand name for amitraz  in some areas of the world. In the U.S. this product is Mitoban (Rx).  Toy breeds are thought to be more susceptible to central nervous system depression from this medication, making use of it in these breeds more of a risk.

The most common recommendation for ivermectin use, currently, is to give it daily, orally, for  at least six weeks and longer, if necessary. There isn't any reason that the dosage couldn't be given by injection but ivermectin injection stings and dogs get tired of it when given at this frequency. The minimum effective dose reported in the literature is 225mcg/kg of body weight once daily. The maximum recommended dosage I have seen is 600mcg/kg of body weight. It is best to start at the lower dose and slowly increase the dosage, if necessary. This is an unapproved use of ivermectin in the United States but I think that many dermatologists feel that ivermectin is safer to use than amitraz and so there is a tendency to use it even though it is unapproved.

Milbemycin (Interceptor Rx) is also reported to kill Demodex mites but is usually a third choice in treatment due to cost and lower success rates. This is an option if you wish to avoid the use of amitraz, though.

If you have to use amitraz it is acceptable to give the dog the antidote for toxicity, yohimbine, prior to dosing with the amitraz. After all, you only need the toxic effect for the mites, not the pet.  Yohimbine has a shorter duration of action than amitraz, so if it is necessary to use yohimbine it may also be necessary to give it more than once.

Administration of antibiotics appropriate for secondary skin infection during therapy for demodecosis helps a lot, in some patients.

Good luck with this. I can provide references for your vet, if necessary.

Mike Richards, DVM
3/12/2000
 

Demodex mites - New treatment?

Question: Have been told Pfizer has a new treatment out for this problem that may be less toxic that Mitaban and Ivamectin.  Unable to find except a new parasitic  trtment for cattle/pigs which said it is not for dogs and can be deadly to them. To continue....my dog has now been put on Ivamectin liquid (into it 3 days). Told it will take a couple weeks or more for it to work, if it does.  Her feet are extremely sensitive, one  hind foot so bad she cant stand to put it on the ground and sometimes falls over. I asked for some type of topical pain med for her feet...told to use an aloe vera cream of some type (fm hlth food store).  She shivers because she hurts and can hardly walk out to do her business very far.   I asked if she shouldn't also be on antibiotic, which seemd to help her when she was having mitaban dips and was told no.  She had one negative scraping after dips, but it has returned with a vengence.  She has a problem with two of her feet bleeing some. Xrays showed calc area, radiologist said may be tumor, etc.  Was refrred to Internal Med Specialist. An ultrasound by Internal Specialist DVM revealed she had a calcified gallbladder (tols not unusual for old dog) and some minor calc. of lungs. Blood tests were not sent with her records. She has been on thyroid med since she was about 2 yrs old when she was properly diagnosed. As a pup and young dog she had many skin probs ...told due to allergies...for which Prednisone was given.  Later, I was given antihistamines to help her thru allergy season...to which she responded well.  Has not had Pred for years now.....and allergies seemed to go away.

Does Pfizer have something new for Canine Demodex ?  HELP.  I love this dog and can't stand to see her suffer  like this... I know she can be a normal happy dog when this problem is taken care of. 2nd half of first msg (if you got it)   THANK YOU IN ADVANCE
 

Answer: C.-

Pfizer has a new medication available, selamectin (Revolution Rx), which
kills sarcoptic mange mites but NOT demodectic mange mites, at least
according to its label. It is fairly closely related to ivermectin, as the
name of it suggests.

Ivermectin is reasonably safe to use for demodectic mange and some
dermatologists use it as a first choice product for this condition now,
despite the fact that amitraz (Mitaban Rx) is the only approved medication
for the treatment of demodecosis. We use it in some of our cases and have
not yet run into a major problem with toxicity.

Whatever you do for the demodex is likely to have be continued long term. In older dogs this disease shows up because there is something causing problems with the dog's immune system. Hyperadrenocorticism, liver disease or major stresses such as cancers are possible underlying causes of the occurrence of demodectic mange in an older dog. In many cases it simply isn't possible to eliminate the underlying cause, so the demodecosis has to be continually suppressed.

I think antibiotics are good idea when there is significant inflammation
and infection around the feet or other areas affected by demodecosis. I
honestly think it helps to resolve the demodecosis to get rid of other
infectious agents for awhile. So I'd tend to be in favor or their use. Ask
your vet about this again.

I don't see any reason not to use pain relief medications, either. It is
important to be sure that there isn't an existing problem that they might
worsen (especially liver disease) but even in that case it is usually
possible to use at least one of the available pain relief medications. Ask
your vet if he or she would like to walk around on feet that look like your
dog's feet look, without pain relievers. If the answer is "no" then ask why
it seems reasonable to expect your dog to do that. Your vet might have a
justifiable concern about pain relief medications but he or she should at
least be able to tell you exactly what that concern is and it should be
important enough to offset the obvious discomfort associated with not using pain relievers.

It is really important to search for the reason that demodecosis has
suddenly appeared in an older dog. I hope you are able to find and treat an
underlying cause because that would give your dog the best chance for
recovering from the demodecosis completely, with treatment.

Good luck with this.

Mike Richards, DVM
12/2/99
 

Mange treatment

Question: Whatever happened to just plain ole sulfur and oil applications for tx of mange.  All the recommended txs I see on all the web sites call for vet visits and expensive drugs. $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$.  Seems the most logical and common sense approach is to try least expensive FIRST, then go the big bucks route.

B. D
 

Answer: B.-

I think that you can tell from reading our web site that we will recommend
inexpensive treatments when they are likely to be helpful.

Motor oil is not safe to use on pets. Since that is usually the oil
recommended by home remedy enthusiasts in my area, I am assuming it is the one you are referring to, too. It is better now than it was when cars
burned leaded gas but it still can cause gastrointestinal problems.

Lime-sulfer dips will kill Sarcoptes mites but not Demodex mites. Other
sulfer containing products do not appear to work for mange based on a
fairly large number of cases I see in which they have already been tried.
They do sometimes help with skin conditions that aren't actually caused by
mange mites but which get called "mange" because people are not aware that this is a description of a specific disease rather than a description of
the symptoms of hairloss and itchiness associated with the mites.

Demodectic mange will often clear up without any treatment at all, making almost any treatment appear successful at times. This is why we recommend not treating this form of mange at all unless it becomes generalized (affects more than five or six spots on the body). If it does become generalized, there is no effective home remedy that I am aware of.

Sarcoptic mange is easier to kill, does not require many visits to treat
and there are safe and effective medications available for treatment. In
this case, a questionable home remedy doesn't make economic sense. It is
cheaper to use an effective medication before secondary complications from the mange sets in.

Michael Richards DVM
12/2/99
 
 

Demodecosis and other problems

Q: Hi...It's me again!  I am the one that wrote you several weeks ago about my 7 month old Boxer that had the Small Intestinal Bacterial Overgrowth, well, now she also has demodectoc mange.  Could this be the reason for the bacterial overgrowth or the intusseception(oops.spelling?)?  We are so upset, because it has been one thing after another with this poor dog and we don't know where to draw the line...Please help!
Thanks,

Mindy
 

 A: Mindy-

It is unlikely that the demodecosis and the intestinal problems are
directly related but multiple problems like this do tend to make me wonder
about underlying genetic disturbances or immune system problems that will lead to continual problems. We have seen puppies who just barely made it to a year old turn into healthy adults and have seen very healthy puppies develop chronic health problems later, so it is possible that some day your problems will slow down. I hope so.

Mike Richards, DVM
 

Mange Mites

Q: Dr. Richards,
      We have a labrador retriever who is 1 year old.  She was recently diagonosed with mites.  She was given antibotics and the situation appeared to be cleared up and "regrowing" the fur that she had lost.  We recently saw the same bald spots on her paws and are wondering if the situtation has come back. Is this possible that we didn't get rid of it all the first time?

The images of these diseases helps identify what may be happening to our dogs. As you know, vet bills can be expensive and having this great tool helps.

Thanks. This website is priceless!!!!

Sharon

A: Sharon-

Unfortunately, it is not unusual for demodecosis to persist or to appear to recur. Sometimes sarcoptic mange will do this, too, especially if there is a source of the mite (like a neighboring dog) that is still there after the
dog is treated the first time. So the best thing to do is have skin scrapings done of the new areas of hairloss and then make a treatment plan based on the results of the skin scrapings.

Mike Richards, DVM
 
 

Demodex - Amitraz

Q: I need Help.  I have a yorkie terrier, which is having a demodex illness. I am in Bangkok,Thailand.  I check with the veterian for MITABAN.  But they don't have in Bangkok.  Is their any alternative on curing my dog.
Thanks
David
 

A: David-

You may be able to find amitraz, the active ingredient of Mitaban (Rx) in
other formulations. It is sold as a peach orchard spray in the United
States and veterinarians used that prior to FDA approval of Mitaban in some instances. Also, ivermectin may be available as it is a commonly used deworming medication for agricultural purposes and it can be used in high dosages with some success. Lastly, milbemycin, a once-monthly heartworm preventative medication, will also kill Demodex mites if given daily for about eight weeks. These are the only other alternatives that I am aware of.

Mike Richards, DVM
 
 

Mange

Q: Dear Dr. Mike,

I have a 2.5 year old male Great Dane, Ike, who was born in Australia in
a farm. No need to say he is very important for me. I work with an
American women's group in Istanbul to help stray dogs. 3 months ago I
adopted 2 puppies from different litters. One was very healthy and the
other was about to die when I found him and his siblings which we
couldn't save. The puppy was diagnosed with distemper and parvo and he
also had mange. Thanks to our vet's efforts he recovered after a long
treatment. His mange treatment started after his recovery from both
diseases as the vet didn't prefer to put too much work on his immune
system. Once the vaccinactions of the other puppy were completed, I had
to bring him home and we tried to keep him seperated from my Great Dane and the puppy. Unfortunately they both contracted mange from him. The healthy puppy had localized demodectic mange with only one patch on her front leg and the other one had generalized demodicosis with several patches all over his body. They had ivomec injections and mitaban dips whilst Ike who wheighs 55 kgs was orally given 3cc ivomec daily and had two mitaban dips every two weeks. I had two mitaban bottles shipped by a petshop in New York for $ 100- a bottle which I found very expensive. Then I had Ectodex (equivalent of Mitaban) shipped from Germany which has a reasonable price. Ike had only two small patches on his body and the hair started to grow soon after we started the treatment, but his back and his neck area are full of small buttons which look like insect bites. Some of these look red like a rash and some look like pimples
which become scabs and sores. He started to lose hair and although his
skin doesn't have any hairless patches, his coat looks awful when looked
in the opposite direction of hair growth in the sunlight. After four
weeks treatment with Ivomec and Mitaban, I gave him an Ectodex dip in
the morning which has to be repeated every week according to its
prescription. In the evening I gave him 3 cc Ivomec orally along with
vitamin E and EFA capsules. He was also on Tavegil to prevent him from
scratching (2 pills daily). It is a medication from Bayer which causes
drowsiness in humans. Half an hour later he vomited and then had somefood and water. I took him out for some fresh air and when we returned home he leaned towards the wall and collapsed with his eyes rolled. He stood up in 10 seconds but he seemed very dizzy and couldn't walk straight. I couldn't find the vet and I didn't want to take him to the
emergency service of an animal hospital as I do not trust the knowledge
and skills of most vets in Turkey. I spent the night at his bed side and
he went to his food bowl many times, but I stopped him with fear of
bloat. I called the vet first thing in the morning. He asked me to stop
the treatment. I always suspected Ivomec to cause appetite loss and
white gums and tongue at Ike, but the vet insisted that it is safe. He
believes that amitraz is the reason for his fainting. He had had his
blood checked the previous morning for liver and it was OK. Yesterday,
he also had carried out a urine test and said Ike has bladder infection
(pH level is 8). Now he is on antibiotics. He switched his diet from
Lamb and Rice to Response Formula from Eukanuba. Ike is also very red
and itchy between the webbing on his paws an toe nail rims. He
prescribed a daily antiseptic bath for his paws, but it didn't seem to
work after 3 days. His eye lids were very swollen and bleeding because
of extreme scratching (I try to stop him, but he scratches at night). Iapplied tea compression and put Terramycin ointment and it seemd to work
well. His eyes look a lot brighter now. I am exceptionally worried for
him and ready to do anything to make him recover. Please let me know if
the teratment was correct so far, should I continue the treatment, what
would cause him to collapse? The vet says we have to continue Ectodex
dips every two months even after he recovers. Is this correct? I am
desperate for an answer. Many thanks.

Engin
 

A: Engin-

Unless demodicosis is caused by a different strain of the mite in Turkey I
have a hard time accepting that it is contagious. Demodecosis is not
considered to be a contagious illness here in the United States. Dogs
affected by generalized demodex have an immune deficiency that allows this normal inhabitant of canine skin to cause serious disease. Since almost all dogs have Demodex mites somewhere on their body but only a few have clinical signs of demodecosis the theory is that dogs don't have to be
infected with the organism because they probably already have it. The
necessary key for disease to occur is immune suppression or immune
incompetance.

It is possible that sarcoptic mange could cause the symptoms you are seeing but it is very susceptible to both amitraz (Mitaban Rx) and ivermectin (Ivomec Rx) and is almost always possible to cure with one or the other of these medications.

Therefore, I think that it would be a really good idea to look for other
causes of the symptoms seen unless a really positive confirmation of
demodecosis is made. If demodecosis has occurred in your older dog, with no previous history, then it is necessary to look very hard for some factor
that is decreasing his immune competance, such as a systemic illness (liver
disease, cancer, etc).

Both ivermectin and amitraz can cause depression, weakness and neurologic signs, so it would be hard to tell which one is the problem. This happens more often with amitraz than with ivermectin but you are using a pretty high dose of ivermectin, making a problem from it more likely. I would be suspicious of the sedative as well if I read the email you sent correctly, since it was given prior to the appearance of the signs.

If it is possible to get a good second opinion, I would advocate doing
this. If that is not possible, at least ask your vet about the possibility
that something else could be going on. Antibiotic therapy may be necessary to combat a secondary skin infection, there may be a fungal illness or a systemic disease with skin manifestations. Unfortunately, to try to help more it would be necessary to examine Ike.

If demodecosis is the problem it is very likely that lifelong maintenance
therapy will be necessary given the difficulty you have had in clearing up
the problem with the treatments already underway.

Mike Richards, DVM
 
 

Demodex

Q: Dr., My Lab/Dane mix has obtained a skin condition in which his skin becomes inflamed, red, and eventually bleeds.  He has this all over his stomach, bottom of his head, and most of all, his paws.  He leaves blood everywhere he sits, lies down or walks.  We've tried everything.  Just so you know, he had puppy mange when he was 3-5 mths old(he;s now 10mths) and the vet treated him with shots and dips, making him more irritated.  The real; problem started with his puppy shots, he has a bad immune system.  His brother lives 2 doors down and has no problems at all.  Our other dog doesn't either.  What should we do? He's a wonderful dog and we need to do something about this problem. Our vet treated him homeopathically and it didn't work.  He was on a medicine called RHUS TOXICODENDRUM and it seemed to get worse.  What can we do? We're
running out of answers and money on him.  Please help us in figuring out what this poor animal has.

Thank You,

Adi

A:  Adi-

I would be really worried about the possibility that your puppy continues
to be infected with Demodex mites based on the symptoms and history in your note.

Skin scrapings to determine if the mites are still present would be a good
first step. In some cases it is necessary to do skin biopsies to confirm
mites when the skin damage has been chronic and severe.

If amitraz (Mitaban Rx) dip causes problems for your puppy there are other treatment options. Our website has information on these. Search using "demodex" or "demodecosis".

It is expensive to treat demodecosis in some cases but usually it can be
cured. There are other possible problems, such as food allergies and immune system disease but the first thing to do is to determine if there are still Demodex mites present causing disease.

Mike Richards, DVM
 
 

Demodectic mange - new treatment options

Q:Hi,

I've been treating 2 dogs for quite some time that were born with demodectic mange.  These puppies (approx. 3 months old at the time) were dumped in a nearby park and my husband and I adopted them and have been treating them for this mite.  We started in September of 1997, treating them with a shampoo of benzoil peroxide and then dipping them with Midoban dip.  We did this every 2 weeks with both animals.  We kind of got off of the "routine" somewhere around November/December and basically had to start all over.

So again we gave them Mitoban dips every other week, along with some
antibiotics to help clear up secondary skin infections and also an EFA -
Essential Fatty Acid supplement.  Of the two dogs (one of which is mostly
chow {The Female} - and one of which is chow and shows some german shepherd {The Male} - we don't know what else they are mixed with.  We were able to get a "negative" skin scraping on the Male dog in April and we were able to get him neutered.  Subsequently, the Female had come into heat just prior to the male's neutering.  I believe that her coming into heat set her back as we are still dipping her and seem to be going through the entire process all over again.

My question to you is...   Do you know anything about Ivermect liquid (for pigs and cows), to be effective in treating demodex mange in dogs?  (by mouth)

My vet has said something about treating the female with monthly heartworm medicine on a daily basis.  She said that sometimes they can get the pharmaceutical companies to donate just out of date medicine and then the vet can pass it on to us.  Have you heard anything on the use of Heartworm medicine to treat this same mange?   Also, can this disease, once cured... come back?  I would think that treating them with something internally would kill something in the bloodstream better than a "topical" dip which doesn't really work that way.  Is that a correct assumption?

Any comments or suggestions you have would be greatly appreciated.

Thank you...
   Michelle C.    (concerned dog owner)
 

A: Michelle-

When amitraz (Mitaban Rx) dipping is not effective in controlling
demodecosis there are two alternatives that may help. The first is
administration of ivermectin either orally or by injection in high dosages.
This use is considered to be experimental for dogs and there have been a
number of suggested dosages, dosing intervals and durations of admistration
suggested for this medication. Your vet will probably have a dosing plan he
or she is comfortable with. We have used ivermectin for this purpose with
good success in several dogs. The other alternative is to give milbemycin
(Interceptor Rx) heartworm preventative on a daily basis at the same dose as
it is given monthly for heartworm prevention. This is also considered to be
an experimental use in dogs. I have not tried this due to the cost of the
tablets but this is also supposed to be helpful in treating demodecosis. If
you have not shaved the dogs prior to dipping with Mitaban you should
consider doing this. It is supposed to work much better when the dogs are
shaved prior to use. There are also suggestions for using amitraz in an
"off-label" manner to increase its effectiveness. Many vets use it weekly
instead of every other week and in desperate situations veterinarians will
sometimes dip the dog daily but only cover half of the body with the dip
each day. We haven't tried this either, but only because we haven't had to yet.

We try to get owners to let us spay female dogs with this condition since
they do often get worse when they go into heat and we have not seen much worsening of the disease due to surgery. It is possible that surgery could induce enough stress to make the Demodex infestation worse but we have not had that experience yet. We do not wait for the infection to be cleared prior to spaying.

Demodecosis can return after an apparent "cure". This normally happens when the dog's immune system is compromised later in life due to an illness or when chronic use of immunosuppressive medications is necessary for another condition. A lot of dogs do not ever have completely negative skin scrapings for this mite but can be well managed with monthly dips or sometimes by dipping at even longer intervals than this. These dogs are always subject to a flare-up of the demodecosis if they are sufficiently stressed.

Good luck managing this situation.

Mike Richards, DVM
 
 

Demodex in Pit Bull pup

Q: Our Pit Bull puppy, who is currently 18 weeks old, was diagnosed with Demodicosis mange around April 10th.  On that visit, our vet showed us under the microscope the mite and told us that she needed to be dipped with Mitaban.  He aslo gave her a steriod shot of cortisone and prescribed two medications (Cephalexin 250mg & Hydroxine).  Two days later, we noticed that she was scratching her self raw on the chest and seemed to be itchy all over.

We took her to an emergency clinic and the vet we saw said that she was going to get a lot worse than before she starts to get better.

We have just taken our puppy in for her second dipping and our vet said that she still has the same number of mites as when we first brought her in.  Two days later, she started scratching herself raw on her chest again and seems to be itching all over...is this normal?  Our vet also gave us a higher dosage of Cephalexin 500mg...do you think this will help?  Is there anything we can possibly do at home to help; like an ointment or lotion?  We are very concerned because she seems to be getting a lot worse.

Something else I am wondering is, if she is having an allergic reation to the Cephalexin, were can I look for a rash if she has mange?  We noticed that she has small bumps, like pimples on her chest.  Could this be a possible allergic reaction?

Any help or information you can provide will be greatly appreciated.

Thank you,

David & Linda

A: David and Linda-

It sometimes takes three or four dips with Mitaban to see a lot of  improvement and it takes at least six or eight dips to cure the condition in most dogs. It is usually not considered to be a good idea to use cortisones in a dog with demodecosis because they suppress the immune response to the mites even further than it is naturally suppressed in dogs susceptible to this problem. I don't know how much effect that has on resistance to treatment but it may have some. In general antibiotics will control the itching within a few days as it is usually from the presence of a bacterial skin infection. If this is not the case by now, it would be a good idea to ask your vet about referral to a veterinary dermatologist for a second opinion on the case. It is not likely that your vet is wrong about the demodectic mange but it is entirely possible that there are two problems present at the same time.

Just in case there is some confusion it is usually considered to be OK to use corticosteroids to control the intense itching when treating for sarcoptic mange, which is a completely different problem than demodecosis.

A soothing bath, such as an oatmeal shampoo bath or a tar and sulfer shampoo bath might help with the itching. Antihistamines help a few dogs and aspirin is even helpful in some cases. Let your vet know the itching continues and if it is severe, definitely consider asking about referral to a veterinary dermatologist if that is possible in the area in which you live.

Mike Richards, DVM
 

Extreme itchiness - Demodex or Allergy

Q: Dear Dr. Mike,

I have an adorable female Boston Terrier "Ruthie", who at around 5 months of age, was diagnosed with demodex mites.  Her ears smelled bad and she was scratching and biting her ears and legs to the point of bleeding.  The vet (vet #1) suggested mitaban dips which seemed to not be very successful.  Several scrapings were done thereafter and the mite was never found again, however she continued to itch.  Eventually sores occurred on her belly and became infected and smelled awful.  He put her on antibiotics and again, the dips.  Again, there was a very temporary period when she seemed to not itch so badly, however the itching did come back.  I had read about a treatment called "milbemycin" and he tried that for 4 weeks, but there was no improvement.  He said that the condition was probably made worse by allergies and eventually gave her an injection of steroids.  Finally, there really seemed to be an immediate improvement...... for about a week or two, then back to the itching.  In the meantime, we moved about 50 miles away and changed vets.  By this time, the dog was almost 1 year old.  The new vet (vet #2) said that she should stay on antibiotics, take steroid pills and discontinue the dips since they had not proved to be very beneficial. She still itched.  He also said, emphatically, that the demodex mites would not cause the terrible itching that she was experiencing and that more than likely she was having allergies.  When I saw no improvement, I called a friend and she recommended her vet highly, so I called him.  He (vet #3) considered all that had been done to her and did four scrapings and did not detect demodex.  He told me that the best approach to treatment of allergies was to do some testing similar to that which is used in humans. She would have to have a large area shaved and have the allergens injected, however, she would have to be off of the steroids for at least 30 days to do this test.  He said that there was a blood test that could be done to identify allergies, but he felt that the first test he mentioned was much better.  We tried to wean her off of the steroids (Prednisolone 5mg.) and when we would get down to 1/2 pill every day, she would begin to itch.  I would add Children's chewable Benadryl, 1 pill two or three times a day. If we could get her down to 1/2 pill of Pred every other day, or less, she would scratch herself bloody.  It looks like we will never be able to keep her off of the "Pred" for the needed 30 days to perform the prescribed test.  I was also giving her a liquid antiobiotic (it looked very much like the stuff I used to give my children).  By mistake, the antibiotic was left down in Florida while we were down there on vacation, and I didn't get anymore when we returned.  That was my oversight.  She didn't get any better, it was the same old story.  I called the vets office, and expressed my concern to his office girl and asked of the vet wanted to see Ruthie. She said the doctor wasn't in that day but she would tell his associate (vet #4) about my concerns, when she returned to the phone, she said that the vet said that the demodex could indeed cause extreme itching and that I should start the mitaban dips again.  I continued the steroids, benadryl, and gave her 4 dips (one every other week)....no real improvement.  Again, when I would try to wean her off the steroids, she would start to itch. Now vet #3 is trying the treatment for sarcoptic mange.  He gave her a shot and gave her a lime sulphur dip.  Should I ask for more antibiotics also?
It's been almost a week, and so far I don't detect any real improvement in the itching.  It is somewhat under control at the moment because she is taking 2.5 mg of the Pred daily and the benadryl as needed.  She is scheduled for 3 more dips.  Basically, it seems that the only thing that relieves her itching at all is the steroid and I am very concerned about long term effects it will have on her.  I really have to consider her quality of life, but I can't help but believe that there must be answer to her problem out there somewhere.  What do you think?  PLEASE HELP ME AND MY BELOVED  RUTHIE.
Jill
 

A: Jill-

Vet #3 (this sounds like the dating game), has proposed a direction for testing that most closely follows what I like to do in these cases. You have several alternatives for dealing with this situation while attempting to come to some conclusions about what is causing the itching. In addition, I tend to agree with the assessment that demodecosis does not normally produce itching of this degree of magnitude except through secondary bacterial infection which should be at least partially controllable with antibiotics. There are exceptions to every rule and I have seen an occasional intensely itchy dog with demodex. Since Mitaban also kills sarcoptic mange in most instances it is possible that there is a dual infection in some dogs. I would consider switching to a hypoallergenic diet, such as the new one Purina has come out with, Hill's i/d, one of the Innovative Diets foods or a homemade diet suggested by your veterinarian. If food allergy is contributing to the problem, removing the offending food may produce a significant reduction in clinical signs in two to four weeks, or possibly slightly longer. You can continue prednisone until it is apparent that there is a reduction in itching, if necessary. Another alternative is to ask for referral to a veterinary dermatologist. Specialists often see the odd presentations of normal diseases and the normal presentations of unusual diseases more than general practitioners. Often they can make a significant difference in cases that have been difficult for general practitioners. If this is an option in your area it would be worth considering. Skin biopsies have been helpful for us, even when we had to leave a dog on cortisones, which do have some effect on the biopsy but often not enough to make it worthless. I agree that the blood test is probably not as accurate as the skin testing for allergies but it can be done while the dog is on prednisone, so you might consider trying it, even though you have to be a little cautious about interpreting the results.

I have to admit that I was taken back just a little by the use of prednisone in a dog that has a previous diagnosis of demodectic mange that may have been generalized. Often, corticosteroids make it possible for the Demodex mites to really cause problems but if this happens they should be easy to find on skin scrapings. Since they aren't, it is probably OK.

Mike Richards, DVM
 
 
 

Breeding dogs with Demodex

Q: If one breeds a dog that has had a case of demodectic mange to another  dog that has had demodectic mange (both localized), is there more of a chance for generalized demodex to occur?
Vince

A: Vince-

If both dogs had demodecosis that was local only and which they recovered fully from, without treatment, then there probably isn't an increased liklihood of generalized demodectic mange in the puppies, based on my understanding of the disease. It would be best to check out their siblings and parents for cases of generalized demodecosis before breeding, though. If either dog was treated with amitraz (Mitaban Rx) or other treatment generally successful at eliminating generalized demodecosis it
is not possible to say whether or not their localized mange would have become generalized. It is quite common for owners to insist on treatment of localized mange and for vets to go along with the demand, to be sure to determine whether this happened, too. If one of the dogs was treated my best recommendation is to avoid this breeding.

Mike Richards, DVM
 
 

Demodectic mange treatment

Q: Dear Dr. Mike; Our 8 month old female boston terrier was diagnosed with demodectic mange. Our vet recommended an ointment named "goodwinol." The puppy has a good appetite and is currently on Pedigree puppy chow, mixed with canned pedigree food. We noticed the loss of hair on her left shoulder and on her left paw about 2 months ago. Our Vet said that two treatments are the ointment, and a more toxic treatment of dipping. Our vet also said that the dog may outgrow the problem. Is our Vet on track with the diagnosis and medication? Thanks; Mike & Carol Staples

A: Mike and Carol-The standard treatment for localized demodectic mange (occurring in less than 5 spots) is to use Goodwinol ointment on the spots and wait for them to disappear. Personally, I don't think Goodwinol ointment does much, so I just tell people to wait and see if the spots disappear and do nothing. Lots of clients aren't comfortable doing nothing, which is probably why Goodwinol continues to be recommended.

Approximately 80% of dogs with localized demodectic mange will outgrow the condition. It is important to know if your pup will outgrow this condition on its own if you intend to breed her. If she does not outgrow it without medication other than Goodwinol and perhaps antibiotics for secondary infections, she should not be bred. If she does outgrow it then it is probably not genetic in origin and it is OK to breed her.

If she does develop generalized demodicosis there is only one approved treatment, which is amitraz (Mitaban Rx) dipping. This works well between 50 and 80% of the time to control generalized mange. When it doesn't work there are alternative unapproved treatments. Check our dog index for more information if you ever need to know more about these treatments.

So, my advice in localized cases of demodecosis is to do nothing and wait. Goodwinol is not harmful, probably isn't helpful but is definitely OK if you need something to do while you wait. Most of the time this will work out OK. If not, there are treatment options.
 

Mike Richards, DVM
 
 

Chronic otitis and Demodex

Q: Dr. Mike, have a one year old Croatian sheepdog. In the past six months she has had 3 ear infections which were treated with Amoxicillin and Panorex. She also had demodectic mange, for this she was given Goodwinol ointment. The ointment did not work, so she was given three mitaban dips every two weeks. The dips seem to have worked so far, her fur is growing back. I was informed that both of these problems can recur. When I asked my veteranarian if there was anything I could do to prevent ear infections, she responded with,"The dog is young and she might have them for the rest of her life." She also could not tell me what was causing the ear infections. I know that my veteranarian can't predict the future, but I do want the best care for my dog, but it can become very expensive with chronic problems. My question is, is it appropriate to ask my veteranarian for a consultation to discuss my concerns so that I can be informed and prepared for what can be done in the future. Or do I continue to bring my dog in for every ear infection and deal with it as a case by case basis?

A: shr- As long as you understand that your vet can only give you an educated opinion about the longterm prognosis of the problems you are seeing I think it is very appropriate to schedule an office visit to discuss these concerns. If your vet feels uncomfortable with this sort of prognosticating it may be worth asking for a referral to a veterinary dermatologist. Most are good about filling owners in on the long term prospects for diseases under their care.

It is possible that the ear infections could be a symptom of the demodecosis. Demodex will sometimes cause otitis. Overall, the chances of clearing up generalized demodecosis with persistant treatment is probably between 50 and 80% somewhere. It can be difficult to do and it is relatively expensive but the odds are good enough that I feel comfortable advising most clients to try for a cure.

Mike Richards DVM
 

Controlling chronic demodecosis

Q: Dear Dr. Mike, We have a three year old mix Border collie that has had severe Mange almost its entire life. Our vet has not been able find a cure for it. We have tried Mitaban, Ivomec, and various othe dips, etc. Do you have any additional ideas we could try? We will try anything! Thanks! Sandy

A: Sandy- There is some indication that long term use of antibiotics is helpful in controlling chronic cases of demodecosis. I am not sure how this works but perhaps relieving the skin of some of the immunologic burden allows it to fight the demodecosis better. Or perhaps a lot of the clinical signs are actually due to secondary bacterial infection. I may be necessary to use antibiotics for months in order to help. The only other medication I can think of for direct control of the mites that you did not mention was milbemycin (Interceptor Rx). This is an expensive option and not always effective, either, but it is another alternative. Some vets are increasing the concentration of amitraz (Mitaban Rx) used but I have not been willing to do this yet as we see some problems with toxicity at the recommended dosages. I do think continuous long term antibiotic usage may be beneficial even when the mites can not be eliminated.
Mike Richards, DVM
 
 
 

Mange

Q: We have a 4 year old chow mix we got from the SPCA. Our vet looked at his skin (specifically his right elbow, right inner thigh and a spot on his back) and told us that it looked to be a classic case of demodectic mites. He scraped off a sample and looked at it under the microscope and told us that he did not find any mites but he doesn't scrape to deep. He gave us an antibiotic and cream to help with the problem. My wife has been reading up on the subject at the local library and is very concerned (to the point of tears) that our beloved animal will die. I have read on the internet several opinions on the subject and found one doctor who seems to believe it is no big deal and others who believe it is. Well is it? Also, without really testing the area again can our doctor be sure it is mites? What else could it be? Do you have any advice on the subject? We will probably take him to a dermatologist in the Dallas area soon to make sure he has mites or to find out what it is that he has. Any advice? Thanks Russ

A: Russ-Going to the dermatologist is the best course of action. If Demodex mites are causing the clinical symptoms it is a big deal in a four year old dog but at least 50% of the cases of chronic generalized demodecosis will respond to treatment satisfactorily and another 30 to 40% of the dogs will respond well enough that the condition can be controlled with chronic use of medications. Demodex is usually pretty easy to find on skin scrapings so I suspect it may not be the problem but once in a while (particularly in shar peis) it can be difficult to find. Sarcoptic mange may also be present. This mange is usually easier to treat and is much harder to find on skin scrapings. Lots of times we have just treated for it hoping to figure out whether it was the problem by the response to treatment. This works often enough that we keep on trying! The dermatologist will be able to give you a better idea which of these problems is present -- or what the problem is if neither mite is likely.

Mike Richards, DVM
 

Golden with demodex and other problems

Q: Hi! My name is Maricarmen, I have a female Golden Retriever and she has 8 months, since she was 4 months she's been diagnosed with hypothyroidism, and malabsorbtion, and anemia. She was first diagnosed with anemia caused by parasites. Then her anemia was cured, her blood level was O.K. now, but then she was diagnosed with malabsorbtion and hypothyroidism. Her hypothyroidism was controlled with a pill but she is still having trouble digesting her food. A month and a half ago she was diagnosed with mange, I don't really remember what kind of mange she has but the veterinarian prescribed Mitaban, and an ointment. I really want to know what you think about her case and what you recommend to me. She has all these troubles but she is a very hyperactive dog. Her mange started in her left paw, with red patches and abrasions , her skin is gray (because of the problems with anemia she had , when she was two - three months her skin wasn't this gray), so she also has like black and white patches. Her hair is falling but I don't know if it is because the heat here in Puerto Rico, or because of the Dip of Mitaban. We have given her 5 Dips ( weekly) and the condition is worst. What can I do is there a better medicine for her? Please write soon we are very worried.

A: Maricarmen- Mitaban is the only approved medication for Demodectic mange. It is not unusual for dogs to look worse after dipping with Mitoban. As it kills the mites and they die in the hair follicles there is often additional hairloss. Antibiotic therapy for secondary infections is very very important in the success of therapy for demdecosis. If your dog is not on antibiotics it would probably help a great deal to add them.

It is highly unusual for a dog to be hypothyroid at this age. It is not unusual for dogs to test "low" on thyroid hormone when they have significant illness of any type, so this may be a misleading lab value in some cases. It usually does not hurt to supplement thyroid hormone but this is worth rechecking.

If the Mitaban (Rx) doesn't work, alternative medications are ivermectin and milbemycin. Neither of these are approved for this use but both have been recommended in the literature.

Mike Richards, DVM
 

Demodicosis

Q: Dr. Mike, Our puppy is about 5 1/2 months old, weighs about 39 pounds, she is part Collie, Husky, Golden Lab, and maybe Shepherd. (A very pretty dog we adopted from the SPCA at age six weeks). When we took her to get spayed the vet said she had mites. Because Teisha had just been spayed she said she could not have the rinses. She prescribed Interceptor flavor tabs. (milbemycin oxime) We gave her weekly doses of that for 4 weeks and she looks much worse. Now she has started getting pustules forming on her tummy, she also has swelling around her mouth. Is there any other way to treat this? Can I apply the rinses at home? It sounds like it will be quite costly to have the rinse applied by the vet... Also what causes the mites? The vet told us it was from stress. Our dog is very well cared for and much loved by my husband, myself and two sons. She is an outside dog. We spend a lot of time with her and take her for walks. She was occasionally tied up in the back yard when she was smaller, but now is loose in a fenced yard. I felt that calling it stress made it sound like she wasn't taken care of or something... What can you tell me about mites and the treatment? Thanks for your help. Debbie

A: Debbie- We dispense amitraz (Mitaban Rx) for clients to use at home. It is important to follow the directions on the package insert and from your veterinarian if you apply this medication yourself. It may work even though milbemycin (Interceptor Rx) did not. There should be no problems relating to the spay surgery at this time with using the dip.

"Stress" is an often misunderstood term. We tend to think of stress as a bad thing and assume that it must have a bad cause. This isn't necessarily true. There can be good stresses. If you don't think so, think back to your wedding day! Stress can be anything that makes your dog's body react to hormonal influences, good or bad. It is very hard to determine what might worry a dog or what might make a dog happy enough to cause "good" stress.

Despite this, I don't know how much stress really has to do with demodicosis in many cases. In generalized demodecosis there is a genetic defect that leads to an inability on the part of the dog's immune system to fight off this mite in most cases. In demodicosis that is not generalized there may be a role played by stress or by some other factor that leads to suppression of the immune system.

Good luck with this.

Mike Richards, DVM
 

Demodex as inherited trait

Q: Hi Dr. Mike, I hope you can help me out again. This time it's a bitch with what has been diagnosed as demodectic mange. The vets told the owner that this type of mange can only be contracted from the mother and that that bitch (mother) should not be bred again as the other pups will also have it. The young bitch was diagnosed when she was a little over one year old. The owners have gone through quite an expense with regular dips of Mita-Ban and 100-day treatment with Ivermectin, etc - with no remission. None of the other pups in the same litter developed anything like this. They are all a little over two years old now and I am in touch with all of the owners. The mother no longer belongs to me (I had co-owned her) and she was bred again just before we heard about this occurrance of the mange. None of the pups in this new litter (they are now one year old) have the problem either. To me, this demodectic mange is not clearly attributable to the mother. Is there any other way of contracting this demodectic mange? Thanks so much. Carla

A: Carla- You didn't mention the breed of the affected puppy -- in some breeds the heritability of demodecosis is pretty well established but in other breeds there is more of a question mark. When it is very important to establish heritability it is generally best not to treat the puppy until the infection is clearly generalized. Many puppies develop localized demodecosis lesions (confined to the head or a couple of areas on the body) and eventually outgrow it as their immune system strengthens. When a puppy does not outgrow the mange or when it spreads to several sites on the body it is most likely to be generalized demodex and is therefore more likely to be an inherited condition thought to occur from a deficiency of a specific type of T-cell. It is tough to make a decision to spay a good bitch or to neuter the sire, or both, when generalized demodecosis appears in a small percentage of puppies in a litter. This definitely could be, is even likely to be, genetic. The mite is present on most dogs but does not cause disease -- so the inherited component in this case is the susceptibility to hairloss and secondary skin infections as a result of overgrowth of the mite population -- NOT the infection with the mites, itself.

The breeds with a known tendency to develop demodecosis include the shar pei, West Highland white terrier, Scottish terrier, English bulldog, Boston terrier, great Dane, Weimaraner, Airedale, Malamute and Afghan. If your dog is one of these breeds, it would be wise to be even more suspicious of an inherited component to this disease.

There are systemic conditions which seem to bring on relapses or new occurrences of demodecosis. Cushing's disease is the most notable but this is present primarily in older dogs. Liver disease seems to be able to predispose dogs to demodecosis and is also more common in older dogs. Any condition causing sufficient immunosuppression can lead to problems with demodicosis so it is always a good idea to look carefully for an underlying cause, especially in a older dog suddenly showing signs of Demodex infestation.

To the best of my knowledge there is no way to prove that demodecosis is occurring due to an inherited tendency in an individual dog, or to disprove this. If the condition is not treated and resolves on its own, that is a good sign that an inherited immunodeficiency is not present but there is no way to tell that in this puppy except that it doesn't sound very plausible with the history given. If the pup had responded well to medications it would be more arguable that the condition was not likely to be genetic.

So that's the best I can do. Even though only one puppy is affected, you have to seriously consider the possiblity of a genetic disorder in the puppy. The decision on breeding or not breeding, considering the rest of the information, such as the low incidence in the two litters, is not mine to make. My sentiments lie with not taking any chances but I am like many veterinarians --- convinced that there are too many dogs in the world as it is and sure that highly selective breeding is best. Many dog breeders have an entirely different outlook on this situation, understandably.

Mike Richards, DVM
 

Demodicosis treatment

Q: demodecosis in 2y old pit bull txed with ivomec 1x already and did well but recurred and now back on ivomec, primor any news on immunoregulin to stim. tcells?

A: salmatt- I do not know of any information that suggests that Immunoregulin (Rx) is helpful in treatment of demodicosis but it may be. We have had pretty good luck using amitraz (Mitaban Rx) for demodecosis and it is currently the only approved treatment. We find that ivermectin (Ivomec Rx) helps in the control of cases that do not seem to be "curable" but have not had a case yet in which it seemed to eliminate the mange entirely. We use it after Mitaban hasn't worked, either, so that may make our success rate lower than someone who uses ivermectin first.
 

Mike Richards, DVM
 

Treatments for demodicosis

Q: Dear Dr. Mike, My husband and I have a thirteen month old chocolate lab. When he was about four months old, he was diagnosed with a generalized case of demodex (he had red, pussy bumps all over his belly). At that time, we were given a generic Keflex for him to take twice a day. Also, we were to take him in for a Mitaban dip every two weeks. We finished his antibiotics and continued his dips for six to eight weeks. Our vet did a skin scrape and found no mites. He gave us a medicated shampoo to use if we saw any more red bumps. Well, at the end of March or early April, the bumps were back on the underside of his neck. There was no puss this time, just scabs. The shampoo did not help at all. When we took him back to the vet, we were told that we may have stopped the dips too soon last time and to give him another round of antibiotics and at least eight more dips. His condition has cleared considerably since we started the dips and finished the pills, but every now and then we see a small patch of hair loss. I'm getting worried that our course of action may not work. Do you have any suggestions for treatment? Should I just keep up the current treatment and hope that his immune system will strengthen and beat the demodex? Will we ever be able to work him at the duck blind or will the marsh water irritate this condition? I'm getting desperate! Any advice you could give would be greatly appreciated. Thanks!

A: Jennifer- There are three potential treatments for demodicosis. The only approved one is the Mitaban (Rx) dip. In some cases it won't completely clear a mite infestation. We usually either ivermectin or milbemycin (Interceptor Rx) when Mitaban fails. Ivermectin is given at high dosages, potentially within the toxic range, for this condition. Despite this, we have not had a toxicity problem yet and feel that it has helped some dogs become mite free-- but not all. Milbemycin is given at the standard heartworm preventative dosage but given daily for 6 to 8 weeks. This can get pretty expensive and we haven't actually tried it yet so I don't have much personal experience to offer. We have usually resorted to using Mitaban and/or ivermectin on a monthly basis to control the Demodex and let the dog live with it.

I don't see any reason why your dog couldn't hunt while affected with demodicosis if it is mostly controlled. You might want to ask your vet about this too. I live very near the Chesapeake Bay and many of my patients spend a great deal of time in the water. I don't remember any complications that seemed to be related to this in demodicosis cases.

The other possibility is that the mites are gone but that your dog has another problem or is simply highly susceptible to staph skin infections. Many Labs are. In these cases, repeated use of antibiotics may be necessary but usually the skin disease can at least be controlled. If allergies or an unrelated immune system problem is present it may be necessary to diagnosis this and try to control it. Getting control of allergies is harder in a dog prone to demodicosis since the use of corticosteroids can make return of the demodicosis a problem. Allergy testing and the use of hyposensitization should be considered for these dogs.

Mike Richards, DVM
 

Demodecosis

Q: My friend has a 10-1/2 year old golden...who was diagnosed with demodex....isn't that a puppy problem? I thought it only happens in puppies....

A: Sonja- Demodecosis is most commonly seen in young puppies between the ages of 3 months and a year. It can occur later in life in dogs that have severe immune compromise for some reason. When it does occur in an older dog, a really good search should be made for some disease that could be causing it. Cushing's disease, liver failure and cancer are possible causes of this in an older dog. I am sure there are others. It may be able to occur just due to a decrease in immune competency with age but I'd still recommend looking hard for another problem.

Mike Richards, DVM

Those pesky demodex mites

Q: On Wednesday, March 26th, my girlfriend and I adopted a chocolate lab/????? mix named Daisy from the Humane Society here in Austin. She was spayed on Tuesday and has just been a sweetheart the past couple of days. We took her yesterday to the vet and had a skin scraping on her head. Sure enough, Demodex mites in a little bald spot. I've been told that this is not contagious to any animal but my roomates want proof and won't let her live with us until they have it. Right now the dog is staying with my girlfriend . This is turning into a big problem and causing a lot of tension in my home. Could you please e-mail me or post a short note explaining what Demodectic Mange is and why it is not dangerous to my roomates. Also, if you have any recommended reading on the subject so I can show them documented proof I would appreciate it very much. Daisy, my girlfriend, and I thank you in advance and look forward to your reply.

A: You'll have to tell your friends that they don't watch enough good TV. Every now and then on channels like the Discovery Channel, there are specials that show the little parasites that live on human beings all the time. The mite that lives in human being's eyebrows is a Demodex mite. Many species have these mites living on their bodies all the time, including humans and dogs. Normally, there is a balance between the parasites ability to reproduce and the host's ability to kill the mites. A few mites live to keep the species going and the host never even knows it.

Unfortunately, an occasional dog does not have the proper set of T-cells to kill the mites. This gives the mites an advantage and they propagate excessively, over-running hair follicles all over the dog's body instead of just around its eyes. The result is hairloss, easily infected skin and the typical appearance of demodicosis (Demodectic mange infestation).

Since almost all dogs already have these mites and since it takes very intimate contact to spread them from dog to dog, this problem is not considered to be a contagious disease. Demodex from dogs does not infect people - nor do Demodex mites from people infect dogs.

Most dogs with only one or two spots of Demodex will outgrow it as their immune system gets stronger with age or decrease in stress. This happens about 80% of the time. The dogs that can not outgrow the problem can be difficult to treat but most of the time this mite can be controlled with persistant effort.

Good luck with this.

Mike Richards, DVM
p.s. -- do your room-mates know about dust mites? Life is full of little microscopic organisms :)

Demodectic mange

Q: Dear Dr. Mike, I have an 8 week old weimaraner puppy who I noticed lately has hair missing around his eyes. He doesn't seem to be itchy. I took him to my regular vet and she did skin scrapings on a few areas but didn't find any mites. She still suspects he has Demodectic mange. She said she usually treats this type of mange with Ivermectin but since she didn't actually see the mites and he is so young she gave me some antibiotics to give him and told me to keep an eyer on it. Is this contagious? Does this mean his immune system is not what it should be? He was shipped from Indiana when he was only 61/2 weeks old and we got him the next day, maybe the stress from such big changes so young made him more susepitble? Any information you can give me would be greatly appreciated. Sincerely

A:  I think that I might be suspicious of Demodectic mange, too -- except that it would be very very unusual in a puppy this young. The mange mite has a 20- 35 days lifecycle, which means that it is very hard for it to cause clinical disease in a puppy that is younger than about 12 weeks of age because it takes a while for the population of mites to grow to sufficient numbers to cause disease. Demodex mites are not contagious. Virtually all dogs have them living in the skin around their eyes. They are passed from mother to puppies and are contagious in that sense but the disease demodicosis occurs only in dogs in which an immune system deficiency allows the mite population to overgrow its normal boundaries and cause disease. I do think that the right thing to do is use the antibiotics, then wait and see what happens at this time. If the eyelids become inflamed or any signs of itchiness or other irritation develop or the hairloss spreads to any other area, take the puppy back to your vet for a re-exam. Hopefully this is just a minor problem associated with all the stress the pup has been through.

Mike Richards, DVM