If you get a friendly -- or not-so-friendly -- nip from an excitable cat or dog don't shrug it off.

"Any pet bite, no matter how superficial it looks, should be checked out immediately," says Lana Conway, a Toronto veterinarian. Here's why: according to the New England Journal of Medicine, four out of five cat bites and one in five dog bites needs medical treatment and infection-fighting drugs.

Dr. Conway offers these tips for nursing a nip:

1. If the bite has punctured the skin, wash the wound thoroughly with hot water, then cover with a sterile bandage.

2. If the wound/scratch appears to be swelling, soak the area in a warm bath of Epsom salts.

3. If the wound continues to look inflamed, visit your doctor right away.

What is Dr. Conway's best advice when dealing with aggressive pets? Avoid a bite altogether by taking proper precautions. When approaching an animal, don't stick out your hand for her to sniff since that's the first thing she'll bite if feeling threatened. Instead, walk up to the animal slowly, hands in your pocket or at your sides, and let her smell you first.