I have a 1 year old male who has been trying to keep a stray male out of our house. (Ironically, the stray is probably his own father!) He has gotten a couple of cuts that have become infected, and they aren't responding to surface treatment. With ten cats looking to me for food and shelter, I can't afford to take them to the vet every time they have something wrong with them!
I'm sorry you're having this problem. What form of cephalexin do you have?
Do you have any other antibiotic?
How badly infected are his wounds? Is there discharge? Is there an abscess?
Yes to the discharge, and yes, it was abscessed. Oh, and I just weighed him, since he has lost weight. His brother Calvin is 10 pounds, he is now only 7 pounds! He has been eating, but he just generally looks unwell.
In weighing him, I just discovered another sore spot, I believe there may be yet another wound! ACK! He has been licking himself, and I would use an Elizabethan ruff, but his brother grooms him every night, so it would be useless.
I would give him 10 mg per pound 2 times daily. You will need to mix it with baby food and syringe feed it to him. Tuna juice will work also.
Make sure he is eating for you as well. The weght loss you describe is not normal for a cat with infected wounds. It makes me think there is another issue going on. He should have a viral test for FELV/FIV.