Bee Sting Treatment for Cats

If the stinger is still in the wound, it should be removed right away. A bee's stinger can continue pumping venom into the wound for up to three minutes after the sting occurs. Gently use the edge of a credit card to scrape the stinger out. If you try to pull it out with tweezers or your fingers, you run the risk of rupturing the venom sac and pushing more venom into the wound.
Once the stinger is removed, keep a close eye on your kitty to watch for signs of a severe reaction. Even if she appears to have a mild, localized reaction, you should still call your vet right away. If she doesn't advise you to bring your cat in to get checked out, she may recommend administering an antihistamine medication, such as diphenhydramine, which will slow your cat's reactions to the histamine released by the venom.
It might be tempting to administer diphenhydramine to your kitty without first consulting a vet, but be cautioned: some over-the-counter medications containing diphenhydramine might also contain other ingredients, such as pain medication, which could be harmful or even fatal to a cat. Your vet will not only advise you on which type of medication is safest, but also on the proper dosage.
For home care, you can treat mild swelling by applying a cold compress or wrapping the affected area with a cool washcloth. Under no circumstances should you give your kitty over-the-counter pain medication, which is poisonous to cats. If your cat appears to be in severe pain, this could be a warning sign of an extreme reaction. If you notice this or any other signs of an allergic response to the sting, get your kitty to either your regular vet or an emergency veterinary clinic ASAP.
It is also a good idea to prevent your cat from bothering the sting spot further. If it is her paw, try and get her to lie down so she doesn't aggravate the wound further. If she is stung in the face, she my try and paw at the sore spot, but it is best to leave it alone. Additional aggravation of the sting could cause additional swelling and pain for your kitty, so keep her calm and try and let her rest as best as she will allow.
Preventing Cats and Bee Stings
Of course, cats can get stung by bees or wasps sometimes no matter what you do, and you can't always prevent wasps or bees sneaking into your home. But there are measures you can take to minimize the risk of your cat getting stung.
If you come across any nests or hives in your yard, have them safely removed by an experienced professional. Corral your cat and any other pets into a room and shut the door should a stinging insect follow you inside. Keep the door closed until you can either kill the insect or shoo it outside. And if your cat has a bug cornered, immediately check to make sure it's not potentially harmful. If her prey turns out to be a wasp or bee, get her away from it and shut her in another room until it can be safely removed. If you use an insect killer to get rid of wasp or beehives make sure that your cat can't get any of it on her as it can make her sick or worse.
A bee sting isn't necessarily cause for panic, but the situation should be treated seriously. By acting quickly and monitoring your cat closely, you may very well end up saving her life.