Mar Vista Animal Medical Center

3850 Grand View Blvd.
Los Angeles, CA 90066




 (Graphic courtesy of Dr. Carol Foil. Used with permission)


Alopecia is the medical term for baldness. A particular type of baldness has been described in the Nordic or double-coated breeds whereby the dog develops symmetrical coat loss on the trunk as well as darkly pigmented skin in the bald areas. This pattern of baldness is commonly called "endocrine alopecia" as it is common in several types of hormone imbalances (in particular, Cushing's Syndrome, Hypothyroidism.)

The condition we call "Alopecia X," however, is not associated with the hormone imbalances that normally create endocrine alopecia. Its causes remain mysterious hence the name "Alopecia X." Given that there are numerous therapies that work for some cases and not for others, and that many of these therapies seem to be in complete opposition, it may be that Alopecia X is not one disease but several and we simply do not know how to distinguish them.

Alopecia X goes by many names:

  • Black skin disease
  • Growth hormone responsive alopecia
  • Castration responsive alopecia
  • The coat funk
  • Pseudo-Cushing's Syndrome
  • Biopsy responsive alopecia
  • Follicular dysplasia of the Siberian husky
  • Adrenal sex hormone alopecia
  • Hair cycle arrest

This web page attempts to create an update of what is currently believed about this confusing condition.




American Eskimo


Siberian Husky


Chow Chow

Norwegian Elkhound

(photocredit first four pictures:

(photocredit last two photos: Wikimedia Creative Commons Graphic)


The typical Alopecia X patient is a Spitz or Nordic breed such as a Chow Chow, Pomeranian, Alaskan Malamute, Elkhound, or similar. Poodles have also been over-represented. Hair loss begins in early adulthood, usually by age 3 years. First the long primary hairs go leaving a fuzzy puppy-like coat but eventually that goes, too. The bald skin becomes hyper pigmented but is not itchy, and the skin does not usually get infected.



Part of the problem is that all hormone-based hair losses can look exactly like this so some testing is needed to determine which of several conditions is present. Expect your veterinarian to begin with:

  • A blood panel
  • A urinalysis
  • Some kind of thyroid testing
  • Some kind of adrenal hormone testing
  • A skin biopsy

The purpose of this rather broad testing is to rule out diseases that look like Alopecia X but for which well-defined treatment protocols exist. This means that two conditions must absolutely be ruled out before proceeding with the trial and error process of Alopecia X treatment:

Both these hormone imbalances lead to "endocrine alopecia" and while they look like Alopecia X, they have their own specific treatments.



This is the same dog as above, after being neutered.
(Graphic courtesy of Dr. Carol Foil. Used with permission) 

Alopecia X seems to be a sex hormone imbalance in at least some cases and did not earn the name "castration responsive alopecia" for nothing. For this reason, the first step in treatment is to sterilize the patient; unspayed females should be spayed, intact males should be neutered. There are health benefits to sterilization regardless of whether or not there is a hair loss issue and many animals will grow their hair back (though possibly not permanently) so this is where we start rather than investing in complex and confusing diagnostics.



What if the pet is already neutered or if several months have gone by after neutering and no hair has regrown? The next simple therapy to try is oral melatonin.

Melatonin can be obtained in 3 mg tablets at most health food stores or vitamin retail outlets. Approximately 50% of dogs will show some response within 6 to 8 weeks. One gives the medication for at least 2 or 3 months before giving up but if hair regrowth occurs, one continues the medication until hair growth seems to have plateaued. After maximal hair regrowth has been achieved, the dose is gradually tapered down to a weekly dose over several months. Some dogs can ultimately discontinue medication though it is important to realize that if one discontinues the medication and the hair falls out again the condition may not be melatonin responsive a second time.

  • Melatonin has been used as a sleep aide. Some owners find the sedating side effect to be unacceptable. Consider giving it at bedtime so that drowsiness is less noticeable.
  • Melantonin should not be used in diabetic patients as it has been found to create insulin resistance.
  • Beware of melatonin brands containing xylitol. Xylitol is an innocuous sugar substitute for people but is a poison for dogs.
  • Since melatonin is a nutritional supplement, rather than a prescription medication, the FDA does not insist on the same quality control it does for drugs. There may be tremendous differences in the amount of melatonin contained in pills between brands. Nature's Bounty® brand has been the preferred brand but any major supplement brand should be acceptable.

If neither sterilization nor melatonin has been fruitful and we know the dog does not have Cushing's disease or Hypothyroidism, then one should realize that the therapies left to still try have potential harmful side effects. One should consider this:

Alopecia X is a cosmetic condition.

It may make the dog look funny, but it does not cause harm.

One will need to weigh the potential side effects of therapy against the appearance of the pet. That said, there are other therapies that can be attempted.


One option in the pursuit of effective alopecia X therapy is the adrenal sex hormone panel available at the University of Tennessee. This test is done by drawing a baseline blood panel, administering a pituitary hormone called ACTH, and drawing a second blood sample an hour later to compare. Samples are shipped to Tennessee for evaluation for numerous adrenal sex hormones. The results show not only what hormones respond abnormally but the university will make suggestions as to which therapy might be likely to work.

Testing is not inexpensive and results can take several weeks to obtain but may help in selecting what therapy makes sense to try next. Often, results are ambiguous and difficult to interpret. Different specialists have different opinions on the usefulness of information obtained.This blood test may be recommended by your veterinarian as part of the Alopecia X work up so we mention it here.


(Photo Credit: NIH Public Image Library)



Lysodren (also called mitotane or OP'ddd) is normally used in the treatment of Cushing's disease which is an excess production of cortisone-type hormones by the adrenal gland. Lysodren acts by eroding the outer layers of the adrenal gland to control cortisone produced by these layers. If the adrenal gland is over-eroded, problems with electrolyte imbalance can occur and potentially these problems can be permanent (though they are treatable). Lysodren helps with Alopecia X because the adrenal gland also produces sex hormones and Lysodren is able to stop the production of these hormones by eroding the part of the adrenal gland that produces them.

It is important to realize that dogs with Alopecia X do not have Cushing's disease and thus do not have an excess of cortisone. Treating these dogs with Lysodren can lead to a cortisone deficiency or, more seriously, the adrenal steroid deficiency called Addison's disease. Signs of lysodren reaction include: listlessness, vomiting, and diarrhea. One should expect periodic blood testing to monitor the cortisone levels being maintained by the patient on lysodren.

Trilostane is another medication used in the treatment of Cushing's syndrome. It has also been successful in treating Alopecia X if the adrenal gland hyperplasia is present. Again, this medication has potential to create a dangerous deficiency in adrenal steroids. It is not without risk even though it has been effective in causing hair regrowth in some patients..



There was a time when this condition was believed to represent a deficiency of growth hormone. Growth hormone is not effective unless given as an injection. It is a genetically engineered product which is often not commercially available but may be obtained through academic sources. Administration can cause diabetes so blood sugars must be monitored. A 6-week course of therapy may produce results that last several years.

There are other drugs that have influence on adrenal hormones and they have been used in the treatment of Alopecia X with mixed results. These other options include: prednisone, anipryl, ketoconazole, leuprolide, and cimetidine. Alopecia X is a frustrating condition and will remain frustrating for years to come. Research is on-going and progress comes gradually.


Deslorelin is a veterinary hormone that curtails the production of both estrogen and testosterone and is usually used to time ovulation in mares. It is available as an implant and was recently tested in Alopecia X. Within 3 months, 75% of the unfettered male dogs experienced hair regrowth. None of the spayed females experienced hair regrowth. No side effects were noted during the one year period of testing. This may pan out as a treatment strategy for unneutered male dogs.


Page last updated: 6/30/2017