Treating open sores on a dog depends upon the type of the sore and the method in which the dog obtained the sore. Frequently, a dog will end up with a sore from a minor injury he received from another dog or from an encounter with a sharp object. While you can use home remedies on minor sores, if a car struck the dog, if it is bleeding heavily or if the sore is inflamed, call a vet.
Muzzle your dog before inspecting the wound. A dog's natural instinct is to snap if he is frightened or if he is in pain. Most open sores are painful and your dog could snap at you or your helpers during the cleaning and treating procedure.
Before you can medicate an open sore, you must clean it. On short hair dogs, washing thoroughly with a mild antibacterial soap and patting dry will remove grime and bacteria. Long hair dogs may require some trimming of the fur around the sore. If this is the case, apply a layer of water soluble gel, such as KY Jelly, to the wound to prevent hair from sticking to the sore, then carefully trim the surrounding hair a couple of inches away from the sore. Proceed to wash the wound.
Apply a dab of antibiotic cream to the sore or dip a clean cloth into a bowl of apple cider vinegar, diluted at the ratio of one part cool water and one part vinegar and lightly dab the saturated cloth on the open sore. Allow the sore to dry uncovered, if possible and repeat the treatment once or twice a day to keep the sore sanitised.
Alternately, dissolve one teaspoon of salt into a cup of warm water and dab that on the sore. You may also use a damp tea bag and place it on the sore for a few minutes. The tannin in the tea will help dry out the sore.
Avoid putting rubbing alcohol or hydrogen peroxide on a dog's open sores unless directed to do so by a veterinarian.
If the sore is located in an area where the dog can't lick it, it is likely to heal once it is clean and treated but most dogs will lick a sore if they can reach it. Dog saliva isn't a miracle cure and the dog may irritate the open sore, making it worse. If this is the case, fit your dog with an inexpensive Elizabethan collar, available at pet supply stores or from the veterinarian's office. This large, rigid plastic cone fits around the dog's neck and prevents it from licking its body. If the sore is on the dog's head, the collar will also protect the wound from being scratched.