The pic is a little blurry, but from what I can tell, it sure looks like canine pappiloma virus (dog warts). It can go away on it's own, but it would take weeks for your pup to clear it by himself. It may spread too, so don't be surprised if you find more in his mouth on his gums. If you notice more in his mouth, you should keep him away from dog parks and doggy daycare or anywhere he might get on contact with a young dog or a dog with compromised immune system.
Storm JUST got rid of most of his warts. He had them for about 2.5 weeks. We took him to the vet to get antibiotics, azithromycin, to help him get rid of it faster, and it really helped. When I asked my vet why anitbiotics for a virus, she said there have been studies in the past couple of years that helped, and it really helped Storm get rid of them faster.
You'll also hear people say you can give L-Lysine to your dog, and when I asked my vet about it, that is usually used to treat herpes or cold sores and some people have used it but I don't believe it's as effective as azithromycin.
Just a warning, if you go to your vet and she gives you an Rx for azithromycin, you do pay full price for it, unless you have some kind of pet insurance that will cover part or all of the cost of meds.
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