If your dog breaks or severely injures a toenail, he's in pain. His nail protects the tissue lying between it and his toe bone, as well as nerves, so a broken or missing nail really hurts. While you might treat a mild tear yourself -- at least until your get your pet to the vet -- a serious nail breakage requires veterinary attention ASAP.
Most toenail injuries result from trauma. While they can occur during exercise outside, such as if your dog catches his foot on a branch, they can just as easily occur inside, such as when a dog catches a nail on carpeting. Dogs who spend most of their lives as couch potatoes are particularly vulnerable since their nails don't wear down as naturally as more active canines' nails. If your dog has torn a nail, he's likely to limp, and you might see blood on the floor. If he's licking a paw a lot, investigate.
Basic First Aid
The Humane Society of the United States recommends basic first aid if your dog tears a nail: With a clean cloth or gauze square, apply pressure to the nail for about five minutes. You can also put some styptic powder on the site. Alternatives include pushing bar soap into the nail or using cornstarch, again applying pressure for five minutes. If the bleeding doesn't stop, wrap your dog's paw and take him to the vet. Any sign of swelling in the paw indicates infection, and your dog needs veterinary attention.
When your dog is in pain, it might not be safe for you to treat even a minor toenail injury. Rather than risk a bite, bring him to the vet. Your vet can sedate your pet, remove the torn nail and bandage it properly. She might prescribe antibiotics to treat or forestall infection, as well as pain medication. Should an infection reach the bone, your dog's toe might require amputation.
Toenail injuries aren't solely the result of trauma. Sometimes, an underlying condition causes the problem. Suspect a medical problem if your dog is constantly tearing toenails or his nails break easily. Among the most common medical issues is lupoid onchodystrophy, an immune-related disorder. Initially, an affected dog loses a nail or two, but over time, all of his nails fall off. The nails that grow back are usually misshapen or brittle, and they eventually fall off again. The dog experiences pain in his paws. Your vet might prescribe long-term antibiotics, along with fatty acid supplements to aid nail growth.