Why a Dog’s Stomach Would Turn Black

Wondering why a dog’s stomach would turn black? People panic when they notice these types of changes in skin color, and for very good reason. Cancer immediately comes to mind, but it’s best not to try and diagnose yourself or your pets online. You’ll start imagining worst case scenarios and worry needlessly.

On the other hand, you might ignore something in need of medical attention. When in doubt, it’s best to seek the advice of a veterinarian, but it’s probably just a normal and/or an easily treatable change known as primary or secondary hyperpigmentation.

What the Vet Said about My Dog’s Black Skin Splotches

Why a Dog's Stomach Would Turn Black
I took the attached photos of black spots on a dog’s stomach. Thankfully my dog didn’t mind having his nap disturbed and pictures taken of his nether region. I still didn’t know why a dog’s skin would turn black. His tummy used to be light pink and didn’t have black splotches, but after spring allergies and lots of itching and licking a few years ago it began turning dark. The surrounding skin on his abdomen and legs turned bright pink and became itchy and irritated. The veterinarian wasn’t at all concerned with the change in color on the dog’s stomach, but she prescribed shampoo for allergens and itching.

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Still wondering why a dog’s stomach would turn black? Causes of hyperpigmentation in dogs include;

  • Skin allergies¬†Why a Dog's Stomach Would Turn Black
  • Yeast or bacterial infection
  • Hormones
  • Contact dermatitis
  • Parasites

Skin Changes Could Be Related to…

I also had an American Eskimo with pure white fur and ivory skin. After spending time in the sun I noticed the sudden appearance of black splotches on the dog’s stomach, back, and sides. I wondered what would cause a dog’s stomach to turn black and brought it up to her vet.

He said that in her case it was caused by the sun. He also said it would never go away, and he was right. Although it didn’t cause health problems the spots never disappeared or lightened.

When wondering why my dog’s stomach is turning black consider his or her age. People develop age spots, and a dog’s skin also changes. Breeds prone to obesity are also prone to hyperpigmentation, especially dachshunds.

My shih-tzu’s stomach didn’t begin turning dark until he was around 8 years old. It happened around the same time he had allergies, but age and time in the sun may have also factored in.

Why a Dog’s Stomach Would Turn Black

Now that you know possible reasons as to why a dog’s stomach would turn black it’s important to consider any other symptoms. It’s up to you to decide if he needs to see the vet, and they should decide the proper course of treatment.

An early veterinary visit may be in order if he’s biting, licking, has lesions, redness, or if he’s ill or seems uncomfortable. Keep in mind that even if the discoloration is secondary (caused by another problem) it’s more than likely harmless and treatable. If black spots are spreading on a dog’s stomach or elsewhere on his skin it’s usually nothing to worry about.


Kimberly Dalessandro (a.k.a. Crystal Ray) began her online writing career in 2005 with PageWise Incorporated and went on to become a top writer for both Associated Content and Yahoo Voices under the pen name Crystal Ray. In early 2017 she launched Blue Crystal Sky ~ Everything Under the Sun. She is continually coming up with new ideas to share with the world.

One thought on “Why a Dog’s Stomach Would Turn Black

  • June 25, 2020 at 1:41 AM

    After reading some of the reasons why black patches could appear on my 10.5 year old shih Tzu stomach I am confident this is related to a skin allergy she has randomly started to suffer from plus she recently had an ear infection.
    We have not fathomed out the causes of her allergy but medication from the vet helps to reduce the severity plus hot sunny weather may be a contributing cause of these black patches.
    Taking into account that she is not scratching or seem uncomfortable plus her age, I am reasonably sure there is nothing to be concerned about but will keep a vigilant eye over the coming weeks to check her progress. It is unsightly but probably a permanent age related condition.

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