Any ideas why my cat has suddenly got bald patches?

[MistyIsland]

My beautiful cat has within the last week suddenly lost a lot of fur on his hind legs, which is now spreading to his belly and front legs.

He’s at the vets Saturday morning (only appointment I could get this week) but just wondered if anyone has ever seen anything like this? Doesn’t seem overly sore and I’ve not caught his excessively licking the area 🤷‍♀️

He’s up to date on his flea and wormers. He’s eating drinking, playing all ok his poo is fine no signs of anything.

I’ve attached a picture of it, started as a really small patch and just got bigger and bigger

One of my cats has this from stress grooming. We use Broadline flea preventer from the vets, so I know it's not a flea allergy. I put a thin layer of vaseline on it, which stops him licking it, then the fur grows back.

Vet thinks it’s an allergy more than likely fleas.

The vet put some flea drops on him and he’s given him a injection to help stop the itch and I have some cream to rub on him.

Have to take him back next week.

I’ve run out of indorex spray (thought the second can was full but wasn’t) so I’ve ordered some more in the meantime daily cleaning for me...