My mother is 79. I got her a dog a couple years ago for companionship. The dog weighed 49 lbs. when I got her and when I took her to the vet a couple months ago she weighed 84 pounds and her cholesterol was over 500, it went off the chart, it could even give an accurate reading.
The vet put the dog on some kind of thyroid medicine, which I don’t know if this could be related to the hair loss or not, but my mother said that the dogs hair is coming out by handfuls. The dog has been on the medicine for approximately 60 days. It is just worrying her to death that the dog could loose all of her hair. This is a very very hairy dog as it is, she is part lab.
I came here hoping that maybe someone would have some kind of opinion as what this could be. It’s Friday evening and the vet doesn’t open until Tuesday so I thought maybe someone here may have some knowledge of this problem.
Dogs do go through regular shedding cycles and in especially hairy dogs it is common for the hair to come out by the handful. If your mother notices visible thinning of the coat (like you can see skin in places you couldn’t before) then the dog should be taken back to the vet.
The high colesterol, weight gaim plus the hair loss in excess of normal shedding sounds like hypo-thyroid to me. We had that problem with our last dog and thyroid medication helped.
It is possible that the thyroid medication is inadequately compensating for the thyroxine deficiency, which means the dog will still show signs of hypothyroidism (like hair loss and weight gain). Or, in a less likely scenario, the dog could be receiving too much medication, thus becoming iatrogenically hyperthyroid. Both hypo and hyper conditions will cause hair loss but by different mechanisms.
As far as I know, levothyroxine does not cause hair loss in and of
itself.
Another thing to consider is Cushing’s syndrome. The hair loss, hypo-thyroidism, high cholesterol all can present in Cushing’s. Other symptoms to look for besides the hair loss, are darkening of the skin, a pot-bellied appearance, excessive drinking and urinating, insatiable hunger, and panting, particularly at night.
If you would like to read up on some of these conditions, here are a few links:
Hyperthyroidism (page is about Feline Hyperthyroidism, but offers excellent explanations about what the thyroid gland does and how it works): http://www.marvistavet.com/html/thyroid.html
I am not a vet, but I believe there are other diseases which cause some sort of hair loss. You might want to look at pages about Demodectic Mange or Ringworm.
If you want an “online diagnosis” kind of thing, that is, asking an actual vet about conditions you describe, you can do so in the Ask The Vet boards of http://www.veterinarypartner.com/
Their library of articles are duplicates of those I’ve linked to above, but you can click on the “Ask A Vet” button, and then after registering (for free) you can post questions, much like this board, that are only answered by veterinarians.
The hair loss you’re describing (hair loss by the “handfuls”) doesn’t really sound like the result of a hypothyroid condition. That disease doesn’t actually cause hair to fall out. Old hairs will fall out in a natural way but simply are not replaced by new ones, thereby causing a bald appearance. This type of gradual alopecia doesn’t appear to be what you are describing.
I’m curious: has your mother reported any improvements in her dog’s general condition since being on the meds? If there has been little improvement and the dog is exhibiting excessive eating and drinking, urination, thinning of skin (to go along with what Calliope said), along with the hair loss, then I would suspect a problem with the adrenal and/or pituitary gland (causing a Cushingnoid syndrome). High cholesterol and weight gain are strongly associated with hypothyroidism in the dog, but without definitive lab findings that conclusively show the hormonal deficiency, the diagnosis shouldn’t be considered final.