When part of a dog’s body looks darker than the rest, it may be caused by an abnormal increase in the skin’s melanin production. This is known as acanthosis nigricans, (Trusted Source) or hyperpigmentation, and it usually appears as thick, velvety brown, and black areas of hairless skin. While some cases are thought to be breed-specific, most cases are usually symptoms of other skin conditions or metabolic problems, like allergies, infections, and endocrine (gland-related) disorders.
By itself, a change in skin color usually isn’t a cause for concern. But it’s important to address the root of the matter to keep your dog happy and healthy.
Primary hyperpigmentation is a breed-specific condition that only affects dachshunds. In other breeds, secondary hyperpigmentation can be triggered by inflammation or friction related to several causes.
🚨 Take your dog to the veterinarian immediately if you spot any suspicious skin growth.
Hyperpigmentation initially appears as a darkening on a dog’s belly, leg, armpit, and groin areas, which tend to receive the most friction. Over time, these areas become inflamed, triggering irritation that causes the dog to scratch themselves and further irritate the skin. This leads to changes like thickened skin, hair loss, odor, and pain. If left untreated, these areas are likely to become infected, worsening the irritation and, subsequently, the other symptoms. In the case of primary hyperpigmentation, symptoms usually appear within the first year of a dog’s life.
Since hyperpigmentation is a symptom of an underlying condition, it’s not uncommon to see it accompanied by other adverse reactions. These include:
There’s no cure for inherited hyperpigmentation. But, you can manage it with soothing topicals like anti-seborrheic shampoo, vitamin E oil, melatonin, and steroid ointments. Early cases of secondary hyperpigmentation will also benefit from these treatments. If your dog’s hyperpigmentation is only cosmetic, treatment might not even be required. However, if your dog’s black spots have become infected, you’ll need to see a vet. They can prescribe you the appropriate antibiotic or antifungal medication. The vet may also recommend topical treatments like medicated shampoo to help soothe your dog’s skin.
No matter what kind of hyperpigmentation your dog is experiencing, it’s always best to get them seen by a veterinarian. A vet will be able to run the appropriate tests and determine the best treatment for your dog. Stay consistent with it, and there’s a good chance your dog’s skin will eventually return to normal over the next few months. In some cases, the pigment never fully returns to normal, but that’s OK, as long as the affected areas aren’t hurting your dog. Trust the treatment and have patience.
The most common type of hyperpigmentation in dogs is called secondary hyperpigmentation. It’s caused by inflammation or friction to the skin resulting from injury, infection, or a hormonal imbalance. Primary hyperpigmentation is a rare breed-based form that only affects Dachshunds.
Treatment differs depending on the underlying cause of the hyperpigmentation. Primary hyperpigmentation is inherited and has no cure. Infections contributing to secondary hyperpigmentation are often treated with antibiotic or antifungal medication. Medicated shampoos and steroids can also provide itch relief.
When you start treating your dog’s hyperpigmentation, it can take weeks or months for their skin to heal and regain its normal appearance. In some cases, the skin may never go back to its original pigment.
If your dog’s skin is bothering them at home, consider giving them a 15-minute oatmeal bath for some natural itch relief. Certain foods like fat-free yogurt are also said to boost dogs’ skin disease resistance. But refrain from feeding them anything new until you ask a vet about it.
