

Ron
Hines DVM PhD
Most
pets that come to me with hair loss have simple problems. Things
like fleas, hot spots, ringworm or allergies. I discuss those problems
in other articles on this web site. But, I also see hair loss problems
that are not as simple. The common point in the not-so-simple hair
loss cases is that the hair loss is identical on both sides of the
body (symmetrical) and the skin is not itchy or inflamed. That tells
me that the problem is coming from within the body – not the
skin.
Some of the conditions that cause this type of hair loss in dogs
are Cushing’s Disease, hypothyroidism, kidney disease, diabetes
and testicular tumors. Those diseases are well understood. However,
there are times, when these diseases are not the cause. The rest
of the causes are poorly understood. Alopecia means lack of hair.
Veterinary dermatologists have called the disease - which is actually
many diseases, Alopecia X. It is also called “Post-clipping
Alopecia” “Growth Hormone Responsive Alopecia”,
“Adult Onset Growth Hormone Deficiency”, “Castration
Responsive Alopecia”, “Adrenal Sex Hormone Alopecia”
“Hair Cycle Arrest” and “Adrenal Hyperplasia-Like
Syndrome”. Pomeranian breeders refer to it as “Black
Skin Disease”, malamute breeders as “Cold Funk”
and Husky breeders as “Follicular Dysplasia”. Post-clipping
alopecia sometimes occurs when a dog's fur is shaved close to the
skin and may not grow back for very long periods. Each term reflects
a snippet of information we know about the condition. It is unknown
if hair fails to grow because of some problem located at the hair
follicles themselves, the lack of certain hormones or the over-abundance
of them.
What Breeds Are Susceptible To Alopecia X ?
Breeds of dogs with very thick coats bred to live in very cold climates
(Nordic dogs) and toy and miniature poodles all have a tendency
toward this problem. I also frequently see it in Pomeranians and
elderly chow chows. It can affect either sex, neutered and un-neutered,
but more often males than females. It can begin before the pet reaches
one year of age or much later in life. Occasionally, dogs with Alopecia
X will re grow their hair with no treatment. This can happen suddenly
- even several years after the problem began. Some dogs seem to
get better only to resume the hair loss at a later date.
What Are The Signs of Alopecia X?
Dogs with Alopecia X come to me with hair loss that is gradual and
symmetrical (the same on both sides of the body). It is usually
worse over the torso and the rear side of the back legs. Hair on
the head, neck and front legs is usually normal and the soft undercoat
of hair these dogs have may be unaffected. It is common for the
skin of these pets to be intensely black.
The
first sign is usually abnormal shedding. Shedding may just stop.
Because these old hairs are not replaces as they should be, the
dog’s coat color fades. Black coats turn gray or reddish,
lack luster and appear dry. Tail hair takes a beating, so the top
of the tail may be the first area noticed.
What
Tests Can Be Run To Diagnose Alopecia X?
A physical examination by your veterinarian as well as breed, age
and history may lead your vet to suspect Alopecia X. To confirm
it, the veterinarian will probably order a blood chemistry profile
and blood cell examination to rule out other causes. The blood profile
will probably include a T-4 value. This assesses the health of the
thyroid gland. A urine examination might be performed as well. If
all these tests come back normal and you wish to pursue the cause
further, an adrenal hormone test to rule out Cushing’s Disease
(ACTH test) and a skin biopsy would probably be suggested.
At this point, some owners elect not to pursue the diagnosis because
their pet seems happy and active. This is a very legitimate decision.
There is no need to feel guilty about it. Not all bald men visit
Bosley. Another thing you should know is that even if medications
work initially , the problem often returns at a later date. Animals
with Alopecia X or any of the previously named conditions should
never be bred. We deal with this disease because people violate
this simple rule for selfish reasons.
What
Treatments Can We Offer?
Neuter
Your Pet
Many cases of Alopecia X resolve when the pet is spayed or neutered.
So this is the first step I recommend. If your dog, or a close relative
of your dog has Alopecia X, it should never be bred anyway. Many
dogs are cured in this way - perhaps half. Should that not occur,
their are other options.
Oral
Melatonin
If your dog is already neutered, or if neutering did not solve the
problem, oral melatonin or melatonin implants may help. About one
in three dogs are helped by it. Melatonin is a hormone produced
in a small structure adjacent to the brain called the pineal body
as well as in other areas of the body. It is important in establishing
daily and seasonal rhythms in all creatures. Many dogs shed and
re-grow their hair coat in a seasonal rhythm as wolves still do.
This may be why some cases of Alopecia X respond well to melatonin
supplements and might give us a hint as to the underlying problem
in Nordic breeds. Some dogs begin to re-grow their hair within 1-3
month of beginning a melatonin supplement. A problem is that we
do not know how to accurately determine the best dose, how frequently
to give it or how long to give it. It does not appear that giving
the standard 3 mg tablets is dangerous. But it some veterinarians
think that giving too much melatonin or giving it over too long
a period can actually make the problem worse. This could be an illusion
in dogs that are not melatonin-responsive and would be loosing more
hair in any case. My suggestion is to begin at a low dose and only
increase the amount if no response is noted. Since this hormone
is designed to pulse and not be continually supplied at a high levels,
it is probably best not to continue giving it after the hair has
returned. If the dog becomes sluggish or shows personality changes,
the dose is probably too high. It should not be used in diabetic
animals. Melatonin itself does not grow hair. But in some cases,
it tricks the body into producing the compounds that do grow hair.
Run An Adrenal Sex Hormone Study
The Veterinary College at the University of Tennessee , and perhaps
other institutions, offer an intensive study of sex hormones and
their building blocks linked to the adrenal glands (ACTH response
test). We believe that abnormalities in the amount of these hormones
in the body, account for some of the cases of Alopecia X. Evaluation
of the blood samples your veterinarian sends to their laboratory
also includes their suggestions as to which hormone therapy might
be effective in your pet.
Whether or not you decide to run this expensive test, at this time,
any further treatment involves putting powerful drugs or hormones
into your pet’s body. I do not suggest any of them but I list
them. I feel that the possibility of side effects is just too great
to justify their use for hair coat problem that are only a cosmetic
annoyance.
A much less dangerous option than powerful medications is to just
manage your pet’s life a bit differently. Dogs with Alopecia
X need more protection against the sun and the cold. Sunscreen and
a sweater can solve that problem. Treating their exposed skin with
a lanolin-containing cream rinse will prevent flaking skin.
Methyltestosterone Supplementation
This hormone has helped some dogs with Alopecia X re-grow hair.
This is perplexing because the removal of circulating testosterone
through neutering surgery in some male dogs with Alopecia X has
also be effective. Testosterone can have many unwanted side effects.
Sometimes, these side effects are reduced when the medication is
given in a slow-release, inject able form. Testosterone often alters
mood. Dogs on this medication may become aggressive. They can also
develop acne, sexual behaviors and liver problems. Testosterone
can also cause the prostate glands of neutered male dogs to enlarge.
In dogs, this can cause problems passing stool. I do not recommend
that it be used.
Lysodren (mitotane,O.p.DDD)
This medication is used to treat over-active adrenal glands that
secrete too much cortisone. Dog’s with Alopecia X do not have
too much cortisone. However, the adrenal glands also produce a variety
of sex hormones and Lysodren will lower or stop their production
as well. So some dogs with Alopecia X will re-grow their hair if
given lysodren. However, the destruction of the pet’s adrenal
gland can be permanent, leading to a serious disease called Addison’s
disease that will require medication for the rest of your pet’s
life. Also, lysodren often cause malaise, nausea, vomiting and diarrhea.
Trilostane, another drug designed to treat adrenal gland disease,
has also been effective. I do not recommend that either be used.
Luprolide
acetate and Goserelin
These are the only compounds that I have used other than melatonin
that do not cause irreversible side effects. They, and the rest
of the compounds in this class are called GNRH agonists. Similar
compounds I have no personal experience with are buserelin, nafarelin,
histrelin and deslorelin. They are probably also safe compounds
because their molecular structure is very similar to the first two.
These compounds all work at the pituitary gland to shut down the
production of hormones related to sexual function. I like to use
them as an alternative to castration since their effect lasts only
a month or so. If the are effective, then castration is likely to
be effective also. But unlike castration, you have done nothing
permanent to your pet.
Growth
Hormone
Some dogs with alopecia X respond to injections of supplemental
growth hormone obtained from pigs or cattle. These are usually young
male adults. The hair loss in these dogs begins at puberty with
the loss of the outer guard hairs of their coat leaving them looking
like puppies. Eventually, they may have no hair left on their neck
or on the rear of their back legs. The skin in these areas usually
becomes very dark. It is difficult to know ahead of time if your
pet would respond to growth hormone because their blood growth hormone
level can appear normal in tests. A growth hormone stimulation test
is available that is more accurate than a simple measure of growth
hormone level. Breeds commonly affected are Pomeranians, chows,
water spaniels, Keeshonds, Samoyeds and smaller poodles. Growth
hormone injections have a high risk of producing diabetes. They
are quite expensive. Coat loss usually reoccurs when the treatment
is discontinued.
Cimetidine
Cimetidine (Tagamet) has helped occasionally and their is no harm
in trying it. Although this medicine is usually used to treat stomach
acidity and peptic ulcers, it is known to increase female hormone
levels. It is sold over-the-counter for heartburn. I have no experience
using it for hair growth problems.
I hope that reading this has given you a better insight into your
pet’s problem. Remember that beauty is only skin deep and
your pet is still just as happy and loves you just as much as before.