Hormonal Skin Disorders of Dogs


Hormonal Skin problems

Question: Dear Dr Michael,

I wrote you in June to ask for some information regarding my dog Lucky who I suspected had some hormonal disturbances after being neutred but I was not really happy with your answer since you only gave me advises as to if he were suffering from mange or fungal skin problems and he had been treated for both fungal with griseolfun and ivermectin for demodectic mange.

Nevertheless, I went to see another doctor since my dog never got healthier.  He  agreed that it was very likely that he had hormonal disturbances after he was neutred, since all the symptoms were present.  He has now been treated with hormones for 3 months, (after 1 month treatment in April with Supertest 0,8 mg injections),the name of the tablets, Andriol, I do not know the contents  since it is not written on the medicine, however he has been medicated with one tablet every 3 days for 2,5 months and is now on  maintenance dose once a week.  His condition has been improving ever since we started the medication.  He is now again on Ivermectin injections, first once a week 3 times and now once every second week.  Scraping was done prior to this medication and demodectic mange was found present, again,  but he did not respond to any medication before we started with the hormones, but now it seems to be effective.

I write to you again, because I am a bit worried that he now gets to much of hormones, because when he gets the tablet once a week he gets very tired just after a short walk to the beach.  His conditions improves within the week and then fall back when taking the tablet.  How will we know when to stop the medication or to slow down even further? This is what I really want to know and also if there is any side effect of the hormones, like why he is in such a bad shape and are somewhat lazy? My other dog has been very patient  with him, but now she seems to think it is enough and wants him to come along and play.

He was neutred in January this year and has suffered ever since, with various skin problems, lack of energy and sometimes high temperature.

When he was neutred he was very healthy, but I had a feeling he had lots of hormones, he almost broke down my gate to be able to get to the streets at night and his penis emerged if we just padded him a bit, which is also the case now.   I find this very strange when explaining that he is actually neutred and cannot have sex, even though it looks like it.....

I read your newsletter today regarding prednisolon and prednil and for a while I gave him treatment for his inflammation, maybe this was totally wrong?  He definitely suffered from kindeyproblem or urinating problem and was very very heavy at that time.  If I administer prednisolon now he immediately reacts with panting and start looses his hair again.

His skin is very dry, I use teethree and oatmeal shampoo for his seborrhea (which I think it is, the doctor is not very specific in that) and occasionally treat him with various oils, like lavendel and his coat will be more soft and develop better.  He also receives a lot of vitamins.

He has still very reddish coat, especially during late afternoon, after the walk to the beach.

Do you have an advice to give me?

Answer: Sissel-

The reason that I did not include information on hormonal disturbances is that the likelihood of your dog actually having a hormonal disorder is very very low. I should have asked you specifically why you thought that hormonal disease was present, instead of trying to point you in another direction first. Even though testosterone deficiency sufficient to cause skin disease (usually bilaterally symetrical hair loss on the sides (flanks)), is considered to be very rare I should have answered your questions concerning the use of testosterone.

I still believe that it is better to concentrate on the demodectic mange and problems secondary to it, at least until it is eliminated as a problem. My best advice on this matter is that it would be better to give ivermectin daily (orally) until the demodex does not show up in skin scrapings anymore. Prednisone and other corticosteroids suppress the immune system and make it hard to cure the demodecosis, so they should not be used, if possible, in a dog with demodectic mange.

A lack of androgens (testosterone and similar hormones) is treated most commonly using methyltestosterone at a dosage of 1mg/kg, up to a maximum dosage of 30 mg, given every 48 hours until hair grows in on all affected areas, then trying for a longer dosing interval such as week, if possible. In many dogs, there will be apparent improvements in hair coat condition, even when testosterone deficiency is not present, due to the direct effect of the testosterone.  It sounds like your vet is following the standard guidelines for this sort of treatment. If you are seeing adverse effects, I honestly think it would be best to stop the treatment and re-evaluate the situation but that is a decision best left to you and your vet, who can evaluate the skin disease present and the response to hormones --- both good and bad -- before making a decision.

Androgen deficiency normally causes approximately equal hair loss or thinning of the hair on both sides as the primary sign, at least according to the information that I can find. I do not have personal experience with this particular sex hormone problem, so I do not know much more than this about it.

Androgen excess, which is a sex hormone dermatosis that is normally responsive to castration, causing hair loss that starts around the rear, gradually spreading to include most of the hair on the trunk and also causing skin color to darken. Usually dogs with this condition seem to be otherwise of normal health.

Neither sex hormone deficiency nor sex hormone excess normally causes a predisposition to demodectic mange, as far as I can find in the literature. However that does not necessarily mean that it is not possible that this happened in your puppy's case.

Side effects of testosterone hormones are most commonly behavioral, usually including aggressive tendencies but other effects have been reported, including lethargy and depression. These effects appear to be dose dependent and decreasing the dosage might be helpful. There have been reports of liver problems with the use of some of the androgenic steroids but this is reported to be uncommon.

If your dog has a sex hormone deficiency, it is unusual to be able to stop the supplementation of hormones, since the problem usually persists life long.

My best advice is to continue to treat the demodectic mange, to consider the possibility of  secondary infections, either bacterial or yeast infections, affecting the skin. Since it may be hard to definitively test for sex hormone deficiency and supplementation may have to be life long, it may be worthwhile to consider taking a break from the medication to see if it is really necessary. The University of Tennessee runs tests for sex hormone levels and it should be possible to mail samples to them from anywhere, if you and your vet are interested in confirming this condition. It would be absolutely necessary to stop the hormone supplementation for several weeks prior to attempting to run these tests, though.

If the information you are looking for is not in this note, please feel free to write back for clarification or to ask for additional information. I was not able to provide much information on the Andriol as that is not a brand name, or generic name, that I am familiar with.

Mike Richards, DVM 12/10/2000    

Hormonal skin disease - Growth-hormone responsive dermatosis

  Question: I have a 4 year old Irish Setter (neutered).  The breeder had told me if I had him neutered it would ruin his coat and she was right.  His coat has faded from mahogany to orange-red and gotten very fine and fluffy.  Now it is shedding to the extreme and is very bare.  My question is, "Why can't he be given a low dose of testosterone as a form of hormone?"  He only had one testicle to begin with but had a beautiful coat, very dark, heavy, and shiny.  My vet has told me she would check into, but says she hasn't had any luck in finding anything out. Would appreciate your help.  

Answer: Martha-

I don't think that you can assume that the changes in the hair coat that you are seeing are due to neutering. That is possible, but there are other conditions that can cause signs similar to those that you are seeing.

Growth-hormone responsive dermatosis causes the symptoms you are seeing. It usually occurs in young adult dogs, causes loss of the guard hairs, causing a "puppy like" coat, which eventually progresses to the point where there are some areas of hair loss, usually around the neck and back of the thighs. The skin in the areas of hair loss may be dark compared to normal skin. Usually there are not systemic signs associated with this problem.

Hyperadrenocorticism and hypothyroidism should also be ruled out in a dog with the symptoms that yours has. Both of these disorders are unusual in young adult dogs but have been seen as young as a year or two of age in some patients. This should be done before trying to rule in or rule out sex hormone and growth hormone responsive dermatoses, because if these conditions are present they can be diagnosed through lab testing and would interfere with the tests for growth hormone responsive dermatoses.  If there is any question about whether this is a hormonal skin disorder, skin biopsies can help to rule out other conditions.

Sex-hormone responsive dermatosis does occur. Normally, there is hairloss in the inquinal region early in sex hormone responsive dermatitis and then hairloss over the flanks and a progression from the rear of the body towards the front of the body.  I don't think that there is a good test for this condition.  It is necessary to supplement hormones and see if there is a beneficial effect to rule in or rule out sex hormone responsive dermatosis. For males, methyltestosterone is usually used at a dosage of 1 mg/kg (up to 30mg maximum) every 48 hours until these is a response to treatment or three months have passed with no response. If there is a response to treatment the length of time between methyltestoterone dosages is increased to the longest interval that will control the problem, usually at least once weekly.

Growth hormone response dematosis is hard to diagnose because the growth hormone levels in serum in affected dogs can be in the normal ranges. A stimulation test is usually necessary to rule this condition in or out. This can be done by measuring baseline values and then using xylazine (Rompun Rx) or clonidine to stimulate production of growth hormone and then drawing follow-up blood samples at regular intervals for a couple of hours. If growth hormone levels do not rise in these tests, a growth hormone responsive dermatosis is likely, if clinical signs are present.

I am assuming that both testicles were located and removed at the time of neutering. If there is any question about this, it may be worth making sure. There are dogs that have skin disease similar to what you are seeing due to Sertoli cell tumors of the testicle, which is more common in retained testicles. Virtually all veterinarians do remove the retained testicle, but I have treated a patient who was supposedly neutered at a young age but had one retained testicle that was not removed.

It is difficult and time consuming to work through all the possibilities when hormonal skin disease signs are present but it is usually possible to identify the problem and to help with it. If your veterinarian is uncomfortable pursuing a diagnosis due to unfamiliarity with these conditions, a veterinary endocrinologist or dermatologist may be able to help and it is possible to ask your vet for referral to a specialist in most areas.

Mike Richards, DVM 10/1/2000


Michael Richards, D.V.M. co-owns a small animal general veterinary practice in rural tidewater Virginia. Dr. Richards graduated from Iowa State University's College of Veterinary Medicine in 1979, and has been in private practice ever since. Dr. Richards has been the director of the PetCare Forum...