Does your dog have a brown or black bump on their body? There are different kinds of lumps and bumps dogs can get, but it’s very likely that your dog just has a skin tag. Here are some quick facts about skin tags on dogs and how (and when) you should have them removed.
According to Merck Veterinary Manual, skin tags are benign, stalk-like growths.¹ They tend to have a wart-like surface and are raisin-like in appearance, usually growing from or around your dog’s hair follicles. These growths can grow alone or show up in groups of multiple skin tags. Any dog breed can develop skin tags, but it's most common in large dog breeds – like German shepherds.
While most skin tags are typically harmless, they can bleed when they’re damaged. This could lead to secondary infections. If an infection is present, skin tags could ooze pus to help purge it out.
The medical term for a skin tag is hamartomas, which help medical professionals describe the excess skin tissue. Typical hamartomas fall into two categories: fibroadnexal or follicular.¹ Fibroadnexal skin tags are hairless and tend to form on the lower legs. Follicular skin tags, as the name implies, form around the hair follicles and tend to be flat masses that grow in groups.
There are some special types of skin tags on dogs that primarily affect senior dogs. One such skin tag is collagenous nevi. These can grow very large on middle-aged and senior dogs’ legs, heads, necks, and other areas that get a lot of friction.¹
The other type of skin tag that senior dogs can develop are fibromas. Fibromas are actually a special type of benign skin tumor that is found in senior dogs.¹ These tumors can be firm and rubbery to touch, or soft and mushy. Regardless of how tough or soft it is, it’s best to have a veterinarian examine your dog’s growth to ultimately determine its diagnosis. Certain breeds are prone to these tumors, including Doberman pinschers, boxers, and golden retrievers.
The exact cause of skin tags is up for debate. Some veterinary experts believe that skin tags and other skin tumors could be caused by exposure to the environment, like solar radiation.¹ Others believe they’re caused by skin cell layers being exposed and constantly rubbed together, given that they tend to form around parts of the legs, neck, and other parts of the body that get a lot of friction.2 Another theory is that skin tags are potentially caused by a genetic predisposition, like many other skin disorders.