Black Spot On Dog’s Anus? Analyzing 4+ Things It Might Be

It’s not a pretty topic, but the world isn’t always rainbows and roses.

Some days, it’s dog fur that is changing color in spots.

Others, it’s about dog poop getting stuck halfway.

And on occasion, we have to talk about canine behinds. We don’t skirt the hard topics.

More specifically– Black spots on dog anuses; what they can be, and what should be done about them.

So, what can a black spot on a dog’s anus signify?

There can actually be a great number of possibilities as to what the dark dot might be. The most likely answer is that it could be something as simple as a freckle or a blackhead, or a sign of the frowned-upon flea.

A black spot on the skin can also be (completely harmless) hyperpigmentation, either developed naturally or influenced by external factors such as exposure to sunlight (so much for ‘where the sun don’t shine”!).

In other scenarios, it can also be a clue that points towards the existence of a more serious condition such as abnormal thyroid levels, allergies, inflammation, hemorrhaging, and additional medical concerns.

If signs such as lethargy, weight gain, bleeding, increased scratching and licking, and development of lumps and bumps are noticed in your dog, it would be a good idea to take it to the vet immediately for a thorough checkup!

What Are The Black Spots On A Dog’s Anus?

Black and white dog's butt and blue sky

Realistically, dogs can develop black specks of varying sizes and shapes anywhere on the body. It just so happens that this time you’ve noticed them around your dog’s bum!

Black spots on a dog’s anus can mean several things. Vets will usually reassure that dark areas on the skin are a normal part of life, but there are some instances where they can be a warning of something more sinister.

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Freckles, Blackheads, Or Age Spots

Let’s start with the most likely possibility: Black spots on a dog’s anus may simply be freckles or blackheads!

Alternatively, if the black blotches are circular and flat but look just like big freckles, they could be age spots that are typically seen in an older dog.

Blackheads usually form when follicles clog. This can happen anywhere on a dog’s body- including near the anus or even on the nipples.

If you think that your dog has blackheads, you can attempt to remove them with a shampoo that contains benzoyl peroxide.

If the dark areas appear to change in color, size, or shape over time, you should contact a vet in the first instance as it could be an indication that something more serious is at hand.


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Clusters of black specks around the anal region may be an indication of another common problem in pets: Fleas!

Black dots that are associated with fleas tend to look a lot like pepper on the skin, and are actually the feces of the parasites. After feeding on the blood of the poor pup, fleas leave their waste behind in order to feed their larvae.

Flea infestations on your dog can either be dealt with at home or by a vet. At home, you can comb through your dog’s coat for the presence of flea dirt, or use a paper towel to catch the specks while you rub your hands through the fur.

It’s also important to get your dog onto some form of flea protection and treatment, such as those from Frontline or Seresto.

If for some reason they don’t work on your dog, or if you’d like to use more natural options, here are some alternative ways to get rid of fleas on your dog and in your home.

Bathing your dog with flea shampoo can also help greatly (just make sure you don’t get it into your pooch’s eyes!). If all of the above methods do not work, consider a call or trip to the vet’s office.


Hyperpigmentation– the proper word for a higher level of melatonin in the skin– appears externally as darkened areas.

Hyperpigmentation or pigment changes can be seen on all parts of a dog’s body, and the areas around the anal sphincter are no exception.

Like in humans, skin changes happen in dogs as they age. Most often, these alterations in pigmentation appear in areas with less fur.

Dog veterinarian Dr. Deb states that skin color changes sometimes occur as a dog matures, even appearing as black spots on a dog’s anus. However, she also asserts that this is normal and that no treatment is necessary.

There are a few possibilities as to what may cause this change in skin color. Conditions such as hormonal changes, allergic reactions, or skin infections can alter melatonin levels in dogs. Hyperpigmentation can even be brought about by a dog being overweight!

If you take another look at the black spots (unpleasant I know, but please do) and see that they are flat and not raised or protruding in any way, then they are most likely just a change in pigment of the anal area tissue.

However, if the black spots are more like masses which stick out from the skin, there is a possibility that they could be adenomas. These are usually composed of fatty tissue or oil-producing glands, and in most cases are thankfully benign.

Whether or not hyperpigmentation is concerning depends largely on your dog’s response to them. If it is increasingly scratching or picking at those spots, you may want to have a vet evaluate more closely.

Abnormal Thyroid Levels

black spot on dog's anus

According to Dr. Scott, DVM, if the anus is not swollen and your dog does not seem uncomfortable, black spots on the anus could indicate abnormal thyroid levels

However, there is no great need to worry about it unless your dog starts gaining weight or losing fur. At that point, it would be imperative to take your pup to the vet for blood work and other tests.

If it turns out that your dog has a low-functioning thyroid, aka hypothyroidism, the vet will most likely prescribe oral replacement thyroid medication.

The dark spots on a dog’s anus are not necessarily a determining factor in this scenario, but they can indicate an issue when combined with other symptoms.

Here are some other signs of low thyroid levels:

Other Possible Triggers


Exposure to the sun can cause black areas to form on your dog’s skin- much like freckles on humans!

As much fur as dogs have, they are not invincible against the ultraviolet rays of the sun. Bare areas in their coats make them especially vulnerable to sunlight.


The black spot on your dog’s anus may be allergy-related. A dog’s skin can react to irritants by changing colors. Dark areas are also possibly a result of scratching due to itchiness, and can increase in size over time.

If the problem persists, your dog may need treatment by a professional vet. Once under control, the black spots on your dog’s anus will most likely change back to their original color- but this may take a span of several months or years.

Medical Problems

Black spots may be a symptom of some medical conditions, such as Cushing’s Disease (overactive adrenal glands) or yeast infections.

Cushing’s Disease

Cushing’s Syndrome is a condition where a tumor in the pituitary gland (in the majority of cases) causes the adrenal glands to excessively produce certain hormones.

It can cause noxious-looking fur along with black spots on the skin. Additional symptoms can include lethargy, increased thirst and appetite, excessive urination, and the development of a pot belly.

Cushing’s disease unsurprisingly needs to be professionally treated by a vet, who will typically do so through the use of medications or surgical procedures.

Fungal Infections
Closeup of dog ear yeast infection

In the case of a fungal infection, a black spot on your dog’s anus may initially look a lot like dirt.

Fungal infections have a tendency to appear in the groin area first, before migrating to other areas of a dog’s skin such as the interdigital zone, anal sacs, and rectum.

Yeast infections are typically caused by an overgrowth of a usually-harmless fungus called Malassezia pachydermatis.

When a dog’s immune system is compromised by underlying conditions such as bacterial infections or allergies, the fungus takes the opportunity to erupt.

How do you know if your dog has a yeast infection? The appearance of multiple symptoms will be a clue. Take your dog to the vet if you notice a foul odor, missing hair, or dry, crusty skin.

Yeast and fungal infections are often treated externally by bathing the dog with a special antifungal shampoo. There are also topical medications that a vet can prescribe to treat such infections.


Dark areas at or around your dog’s anus may be a symptom of a problem with the anal glands.

Anal glands are located on each side of the anus, and can become infected if they become impacted due to the canine not being able to release them properly during bowel movements.

This will result in irritation and inflammation, which is often noticed via a fishy, foul smell– as well as the tendency for a dog to drag its bottom (or ‘scoot’) on the ground in an almost comical manner.

The black color is often a response to the swelling. If a dog has swollen glands that are unable to be naturally released, a trip to the vet may be advisable. The vet will be able to express the glands and empty them, getting rid of the smell (but not always!).


Dark spots can appear as bruises, which are usually caused by bleeding under the skin. Underlying blood capillaries that are ruptured and which release blood into the affected tissue areas cause the skin to retain a dark discoloration.

Bruises usually disappear on their own, but if they persist or get darker, you should take your dog to the vet ASAP for evaluation.


Putting clothes on a dog can cause dark spots to form due to the rubbing and friction, though this mainly occurs under the ‘armpits’ and limbs.

If there is any fabric or material near your dog’s anus (like a doggy diaper), it is conceivable that constant abrasion may have caused dark grazes to form.

If I Find Little Black Dots On My Dog’s Anus, Should I Take It To The Vet?

Corgi butt on outdoor adventure

Realistically, black dots that appear in your dog’s anal region which aren’t raised or bumpy are most likely either going to be freckles, hyperpigmentation, or age-related spots.

All three of these possibilities are completely natural and harmless, and there will be nothing further that an owner would need to do in regards to their pooch’s speckled behind.

Fleas and blackheads are also a likelihood, but both of these problems are minor enough that you don’t need to pay a visit to the vet. Using an effective flea treatment and suitable shampoo will enable you to get rid of these ailments very quickly.

Now to the parts that warrant a professional evaluation: The existence of the following symptoms in addition to black spots on your dog’s anus may indicate a more severe problem being present. Consider these signs a priority:

  • Sudden changes in color or feel of skin
  • Thinning or loss of fur
  • Increase in itching and scratching
  • Bleeding
  • Lumps and bumps that contain fluid
  • Scaly patches of skin that are thick and crusty
  • Weight gain
  • Lethargy

If you notice any of these symptoms, take your dog to see the vet immediately.

Even if it doesn’t exhibit these signs, don’t hesitate to seek the advice of a professional if you don’t feel completely at ease about the black spot on your dog’s anus. It’s always better to be safe than sorry!

Check Out These Articles

My Dog Has A Rash Near His Private Area: Causes & Treatment
Pink Spot on My Dog Nose: Causes & RemediesHow to Treat a Limping Dog at Home (& When to take to the vet)
Dog Poops in Sleep: Should I be Worried?Hard Bump on Bridge of Dog’s Nose? Causes, Pictures & TreatmentWhy is My Dog Limping After Laying Down? Reasons & Treatment at Home

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