Cat hair loss

[Gillz88uk]

I noticed a bald patch on my cat's shoulder today. The hair was falling out in clumps as he groomed and even as I stroked him. The patch is still small, and I didn't notice anything out of the ordinary yesterday, so I'm sure this is a new developement. There is nothing in his environment that would be causing any stress to him, and he hasn't been grooming more than usual lately. His diet consists of Whiskas sachets and occasionally a small amount of tuna. He has been ignoring the Iams dried food we leave out for him. He is a 16 year old domestic shorthair and has been spending a lot of time indoors lately due to bad weather, although he is still an active cat, and goes outside when he can. He has another bald patch on his neck, which developed a few years ago due to an allergic reaction to a flea collar. He was recently treated with canac flea drops, and he doesn't have fleas. What could be causing this hair localised hair loss?

[petal54]

have you been to the vets?also,if indoors & heating on could be effecting him.is he scratching alot?could be ring worm.sorry not much help