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The appearance of black spots on dogs skin can lead many pet owners to worry about their dog’s health.

While some dogs are born with dark patches, others develop them later in life.

What are they and what causes them? Are they safe or harmful to your dog, and most importantly, should you be concerned?

These are some of the questions that many pet owners wonder about.

In this article, we will attempt to shed some light on this mysterious subject by answering these questions and more.

Here’s what you’ll learn in this article:

What Are Black Spots on Dog Skin?

Black spots occur to altered pigmentation of the skin and can appear anywhere on a dog’s body, including the belly, tail, legs, and so forth. In many causes, these black patches are found on dogs with rashes and are often accompanied by hair loss around the area.

In most cases, black spots on the skin are a natural occurrence and should not cause concern. However, if the spots appear to be inflamed or swollen, it could be a sign of underlying issues, in which case, it is best to consult with your vet in order to evaluate the cause of the black spots.

Common Causes of Black Spots on Dogs Skin

Black spots can appear on a dog’s skin for a variety of reasons. While it is strongly advised to schedule a visit with licensed vet to properly evaluate the situation, here are some of the most common causes of black spots on dogs skin:

Natural Aging

It is common for black patches to appear on a dog’s belly due to natural aging. As a dog becomes older, the spots may gradually darken with age. In most cases, you should not worry about spots caused by aging; however, if the spots appear scaly, swollen, inflamed, or are are accompanied by hair loss, it may indicate underlying issues.

Flea dermatitis

A significant proportion of dogs are allergic to fleas, and an encounter with one or two fleas is enough to cause a reaction commonly referred to as “Flea Dirt.” The skin reaction often first manifests as multiple small black spots on the dogs’ skin, which can progress to serious skin inflammation and fur loss. The treatment requires getting rid of all of the fleas on the dog and in the dog’s environment and possibly antibiotics. One study showed that 100% of dogs with flea dermatitis that were treated with a Seresto collar had their condition completely clear up within 30 days of application.

Food Allergies

Food allergies that don’t result in an overt yeast infection can also cause black spots to develop on the dog’s belly. Symptoms of food allergies in dogs don’t resemble symptoms of food allergies in humans. Allergic dogs rarely exhibit gastrointestinal upset and instead suffer from repeated ear infections, skin infections, and irritated skin. Affected dogs will chew obsessively on their paws and other parts of their bodies.

Veterinarians can do allergy testing to guide decisions about food. Still, the easiest way to deal with this situation is to look at the main ingredients in the dog’s current diet and switch to a limited ingredient diet that doesn’t include those ingredients.


Melanoma is rare in dogs, and most cases develop inside their mouths or on their toes. However, on rare occasions, a pigmented spot that develops on the dog’s skin is a melanoma.


Macules are round, flat, pigmented areas that develop after a skin infection. The area is usually red and inflamed before turning into a macule. Macules don’t require treatment, but the underlying skin infection may require antibiotics.

Yeast Infection

If the black spots are accompanied by excessive itching or a strange odor, yeast infection may be the culprit. The symptoms often include black spots in the groin area, scratching, chewing and biting at the paws, an unpleasant odor, and sometimes a greasy coat. Yeast infections can be cleared up with medicated shampoos, but most are caused by an underlying food allergy and will keep returning unless an appropriate diet change is made.

Sarcoptic Mange

Mange is caused by mites burrowing into the skin. It can cause hair loss, skin irritation, and the formation of black spots. The mites are carried by foxes and can be transmitted to dogs through environmental contact. Mange is easily treated with oral and topical ivermectin, although it can take time for the lost fur to re-grow.

How to Address Black Spots on Your Dog’s Skin

If your dog suddenly starts to develop black spots on its skin, it is important to visit your veterinarian. While in many cases, it is nothing but a normal part of the aging process, in other cases, medical treatment of the underlying cause is necessary. Most of the conditions that cause black spots are easy to treat.