I was hoping to hear back from you with some additional information about Tommy, but I can answer your question now and if you need any additional information, just click 'Reply.'
There can be various causes for a cat to lose his hair. If the hair loss is concentrated in small areas, where the skin is red and scaly, this could be a fungal infection called ringworm. If this is the case, it is very contagious to other cats and humans. Here is more information about ringworm:
Some other causes of hair loss may be external parasites like fleas and mites, which cause itching, food or environmental allergies, underlying medical conditions (especially in a 'senior' cat like Tommy) like diabetes and hyperthyroidism, and psychogenic alopecia, where a cat will lick excessively or pull out fur on his own. If a cat is in pain, he may also lick excessively at the site of the pain, whether external or internal. Here is more detailed information about hair loss in cats:
Sometimes, dry skin, due to a nutritional deficiency can also cause dry skin and fur causing hair loss and a supplement like Omega 3 might help. You can offer oil from canned tuna, salmon or sardines, or buy Alaskan Salmon Oil at your pet supply store and add it to his food.
The only way to know for sure what is causing the hair loss is to have Tommy evaluated in person by his vet for a definite diagnosis and treatment, if needed. The vet might even take a skin scraping (painless) to analyze some skin cells under the microscope to provide more diagnostic tools.
I hope all will be well with Tommy and please let me know how he's doing and what the vet tells you. Thanks!
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