Cat has wounds from unknown source

A preface: he has an appointment Monday! My cat who is a year and a half old has two wounds he won’t stop licking on his front leg and back leg, each about the size of a quarter. We do not let him outside, and it doesn’t seem to be related to any scratches from our other indoor cat. We did recently change his food, and haven’t had time to change it back to his old food. These wounds both popped up within the last three days. We’re keeping an eye on the wounds and we have a cone we ordered to put on him that’s coming in today (Friday 11/3). Any ideas of what it could be? TIA

Hello!   I have a few suggestions.  You've said that this is being licked, so it is most likely itchy or painful.  Sometimes, the licking causes the lesion - for example, in the case of an itch due to allergy, or over a painful joint.  Some illnesses e.g. urea from kidney failure, common in older cats, can thus lead to unexpected ulcers in strange places e.g. because of changes to the underlying blood supply.  Ringworm is not typically associated with licking, but can be.  Other times, there is a pre-existing lesion and the licking simply makes it worse. Examples of this would include parasite bites (fleas / mites), fly-bites, a physical injury e.g. burn, a larger bite wound e.g. mouse; a scrape e.g. after a fall from a chair; a foreign body such as a grass seed or some other cause of a small abscess.  Generally, cancer doesn't itch or hurt, although sometimes cats lick if it's painful.  Your cat would be unlucky for that sort of thing at such an age.   I hope that this gives you a few ideas; it can sometimes be surprisingly hard to tell what started a superficial licked area.  I think that itching has even been caused by anxiety in some animals (although in many such individuals, it could be caused by undetected pain).  Certainly, anxiety compounds licking habits.  You have an appointment so it sounds as though your vet might have triaged the situation already. Please will you let us know if you get to the bottom of it?

Hi, I agree it was probably the licking that caused the lesion. https://www.minimilitia.mobi/ https://www.applock.ooo/