Hairloss in cats may be caused by a number of factors, but the pattern and the amount of skin irritation associated with the hairloss can be indicative of the cause. The vast majority of skin problems can be attributed to allergies, and the one we see the most is flea allergy. You do not need to see live fleas to have a case of flea allergy. Even one bite by a flea in an environment the cat has visited is enough to set off a chain of inflammation that causes an itchy rash, crusty inflammatory lesions and significant patchy hairloss. The most common location we see flea allergy dermatitis, is around the haunches and tailbase, or around the neck and chin but it can crop up anywhere.
Mosquito bite allergy is another cause of hairloss and itchy skin. This is also often seen around the face and chin. Without doing a flea control trial with a quick acting parasiticide (such as Bravecto topspot) – one that kills fleas BEFORE they have a chance to bite, you are not ever going to know if the cause of your cat’s itchy skin and hairloss is due a flea allergy, as the fleas could be in the places your cat is visiting, but not actually be living on your cat’s body at all.
Another important cause of hairloss is a syndrome termed eosinophilic granuloma complex. This usually manifests as red itchy patches and hairloss over the inner thighs, belly, and sore swollen ulcers on the tongue, or nose and lips. If you suspect your cat may have this syndrome, please call us and we can discuss how to first diagnose and then manage it.
Hairloss without associated skin irritation can often be due to behavioural factors. Cats who are stressed or in pain may overgroom themselves in an effort to self-sooth (much like we would suck our thumbs as babies or bite our fingernails as adults). This type of hair loss feels spikey to touch due the broken hair shafts and the skin usually looks essentially normal. If you suspect your cat may be suffering from this type of hairloss, they may need investigation for painful conditions such as arthritis, urinary disorders, or for stress and anxiety disorders.