My cat's lip is swollen and he's sneezing. Is it allergies? Can I use Benadryl?

Benadryl will not help, it's probably allergy related indeed, it's a common problem in cats (may be autoimmune related as well), as long as it does not bother him there is usually no reason to treat it, if it gets worse or affects his appetite you will need to take him to the vet for a steroid injection.

I am sorry to hear that! I do think going to the vet would be a good idea. Cats can get many types of lumps at their mouths. From your description one thing I would want to rule out is eosinophilic plaques. These can be caused by allergies so getting on a low allergen food (I would recommend prescription due to cross-contamination at the manufacturing level) and medications can be vital! Of course it is hard to tell without looking at her so your vet may want to rule tests or take a biopsy first! I hope this helps!

This looks to be a rodent ulcer (eosinophilic granuloma complex). She really needs to see a vet for this issue. This is not something you can treat with over the counter medications. Also, there are not many over the counter medications that are safe for cats. These lesions are treated, typically, with antibiotics and steroids. Likely the reason for it is hereditary or an underlying allergy. Please refer to this article for further information. ( https://www.thesprucepets.com/rodent-ulcers-in-cats-5093328 ) The sneezing is not likely related to the swollen lips. That seems to be a separate issue. Either way, Luna needs to see a vet.

This is a common look for cats who are allergic to their food bowls -- if any of his bowls are plastic, I'd recommend switching them out for glass and washing daily (or at least every other day). It could be caused by other allergies or a bug bite as well, and often goes away on it's own. If switching bowls (if applicable) and giving it a week doesn't make it go away, I'd recommend a vet visit.

From the photos it looks like Xena has a "rodent ulcer" (aka: eosinophilic granuloma complex). It is best to have her checked out by your regular veterinarian to get a definitive diagnosis and treatment. ( https://veterinarypartner.vin.com/default.aspx?pid=19239&id=4951528 ) Hope this helps. Best wishes.

She could have an eosinophilic granuloma which is common in cats and can be caused by an allergic response. The lesion may become ulcerated and is typically treated with a corticosteroid. If she has any fleas then she should be treated for fleas. You could also put her on a hypoallergenic diet and see if that helps. Try to find a low cost clinic or a vet that would take a payment plan so you can get her treated. If she just needs a corticosteroid then it shouldn't be very expensive. Hope she gets better soon!

I can see that Cocoa has swelling of her lower lip. This is a sign of an allergic reaction, which is pretty rare. I recommend calling your vet to let them know what is going on, and holding off on the next dose of Clavamox until Cocoa is seen by a vet. The lip swelling is not life threatening, but if Cocoa develops trouble breathing it can be very dangerous. If you believe that she is having trouble breathing, she should be seen by a vet immediately.