Acute moist dermatitis: How to manage hot spots in dogs

If you’ve ever noticed your dog frantically chewing, licking, or scratching a particular spot on his skin, it’s possible he developed a condition called acute moist dermatitis, also commonly known as “hot spots”. These moist, red, and often very painful sores can appear out of nowhere and can be, understandably, quite alarming. 

Because licking the irritated skin is a natural instinct, acute moist dermatitis can affect any breed and all life stages. And it’s also one of the reason why it’s a common.

Whether you’re a seasoned pet parent or a newbie in the world of dog ownership, I want to help you better understand this extremely uncomfortable disease. I firmly believe that the more you know about your pup, the better you are equipped to help him lead a happy and healthy life 🥰

So here’s everything you need to know about acute moist dermatitis in dogs 🙂

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While I am a veterinarian, this article is not intended to replace professional veterinary advice. If you have any medical concerns about your pet, consult your vet immediately. Always seek professional assistance if you are unsure of your pet’s health.

brown dog biting and scratching his front leg

What is acute moist dermatitis in dogs?

Acute moist dermatitis, also called pyotraumatic dermatitis or ‘hot spots’, are localized skin inflammations. 

These inflamed lesions are red, swollen, wet, and sometimes oozing pus. They usually appear suddenly and can become very painful. 

Sometimes they are obvious, other times they can be hidden in fur and you have to search your pup’s fur to see the reason why is he so irritated. 

While there is usually an underlying condition that causes the primal skin irritation, hot spots are wounds inflicted by self-trauma. 

When a dog licks a sore spot or an itch, it stimulates more itching and irritation, causing him to bite, lick, or scratch the skin sores even more. It’s a vicious self-harm cycle, that often results in inflammation, secondary bacterial infection, and an open wound. 

Symptoms of hot spots in dogs:

Hot spots typically present with the following clinical signs:

  • Redness and inflammation: The affected area appears red, and inflamed, and may feel warm to the touch.
  • Moist or oozing sores: Hot spots are often characterized by a moist appearance due to the dog’s persistent licking or chewing, which can lead to oozing sores. In case of an advanced bacterial infection, the sores can contain or ooze pus.
  • Foul odor: Bacterial growth or fungal infection can cause foul odor of the wound.
  • Matted hair or hair loss: Hair in and around the hot spot may be matted, sparse, or completely absent. 
  • Pain and itchiness: Hot spots are itchy and painful. Dogs with hot spots frequently exhibit signs of discomfort and pain, including itching, scratching, and even behavioral changes. The discomfort caused by hot spots can also lead to increased agitation and restlessness.

Hot spots can dramatically increase in size in very short period of time. Especially if you leave your dog alone, a skin sore can turn into a painful lesion. 

Brown dog scratching his head

The most common causes of acute moist dermatitis in dogs

Basically, any skin irritation that causes your dog to lick the affected area has the potential to become an inflamed hot spot.

The constant licking and biting keeps the wound wet, which creates a breeding ground for bacteria. And if your dog’s fur becomes matted and entangled in the wound, it further promotes the inflammation. 

While hot spots can appear anytime, warm weather and higher humidity can have a somewhat seasonal effect.  

As I said before, any skin irritation has the potential to become a hot spot. However, there are a few health issues that often cause acute moist dermatitis:


Allergies, whether food-related or environmental, often cause intense itching and skin irritation. The most common are food allergies and flea allergy. 

External parasites:

Flea or insect bite, as well as other external parasites, are often the primary cause of hot spots. Make sure your dog is protected, especially during the summer months. 

Anal gland problems: 

Anal sac disease, inflamed or full annal glands are itchy, uncomfortable, painful, and annoying. If your dog starts to lick or bite excessively at his bottom or around the tail base or starts scooting, take him to a vet to make sure he doesn’t need his glands expressed. 


Dogs tend to lick or bite around painful joints, much like humans rub the sore knee, to alleviate the pain. 

On top of that, dogs with painful joints or back pain tend to lie down more, which can create abrasions over bony pressure points. If a dog licks this abrasion, it can quickly escalate into a full-blown hot spot. 

If you have a dog with arthritis, learn how to properly manage his condition. 

If you have a senior dog with low muscle mass, make sure he has a comfy soft dog bed to lie on. 

Otitis externa:

Bacterial or yeast ear infections can be very irritating and painful, causing the dog to scratch excessively at his ear. Depending on your pup’s reach, he can create an open wound on his ear, neck, head, or ear base. 

Skin diseases:

Any skin disease that causes itching or pain has the potential to cause hot spots in dogs. For example, canine atopic dermatitis is a common allergic skin disease that causes severe itching. 


Dogs, just like other animals, have a natural instinct to lick their wounds. It’s like when you rub your head when you hit it. It elevates the pain a bit and helps clean debris out of the wound. And dog saliva has a very mild antibacterial effect.

But, any damage to the skin can lead to the formation of hot spots in dogs, if the licking becomes excessive or obsessive. 

Poor grooming:

Now that we covered health issues as the main causes of acute moist dermatitis, let’s move on to some not-so-obvious reasons why it can happen. 

Matted fur is itchy and uncomfortable. Dogs tend to pull and bite at the tangled knots, creating small lesions. And so the itch-scratch cycle begins. 

During warm or humid weather matted fur prevents air from reaching the skin. The skin cannot “breathe” properly and can get infected. 

And if you bathe a dog with a matted coat, or if he goes swimming, or gets wet from rain, the skin underneath will stay wet for a long time. 

Wet or damp skin is prone to bacterial infections. This makes some long-coat breeds more susceptible than others.  

Behavioral issues: 

Anxiety, OCD, and other behavioral problems can cause excessive licking or scratching. 

Even boredom can lead to scratching, biting, and self-mutilation.  

Infographic: The most common causes of acute moist dermatitis in dogs

How to treat acute moist dermatitis in dogs

Once you identified hot spots, I would highly recommend booking an appointment at your local veterinary clinic. 

The first thing we need to do is stop your pup from scratching and making the situation worse. Your pup will need an Elizabethan collar, commonly known as an E-collar or ‘cone of shame’, to prevent him from reaching those itchy places. 

Btw. here’s a guide on how to make a dog with a cone more comfortable. They all hate those things, I know 😟 But it’s cruicial that your pup cannot scratch or lick his lesions.

Topical therapy:

We begin by removing the matted hair around and above the hot spot – this is usually done by removing the hair and carefully shaving the area of skin around the wound with clippers. 

Now we can examine the wound.

The affected area needs to be cleaned with sterile saline and a mild antiseptic solution. The painful lesion is gently patted dry and left uncovered to dry. 

Topical medication (creams, sprays, or ointments) can help prevent or treat secondary bacterial infections, promote wound healing and calm the itchy skin. 


In severe cases with deeper skin infection the patient needs injected or oral medications to help treat the condition. 

Your pup might get antibiotics and anti-inflammatory medications to help treat the infection. 

Corticosteroids can be used to reduce inflammation, redness, and itching associated with hot spots. 

Anti-itch medication is necessary especially in cases where the itching and the resulting self-induced trauma are severe. 

In cases where allergies are a contributing factor, antihistamines can help alleviate itching.

Hot spots can be quite painful, so your veterinarian may recommend pain relief medications to keep your dog comfortable during the healing process.

If your dog is reacting to flea bites, your vet will also administer flea treatment and tell you how to get rid of fleas effectively. 

Addressing the underlying issues:

Identifying and addressing the underlying cause of the hot spot is vital. If allergies, skin infections, or irritants triggered the condition, addressing these issues is key to preventing recurrent hot spots. 

Your veterinarian may recommend dietary changes, tick or flea control, or allergen-specific treatments as needed.

During the treatment phase, it’s crucial to prevent further hot spots from developing. Regular grooming, maintaining a dry coat, and avoiding excessive moisture on your dog’s skin can help.

Regular follow-up visits with your veterinarian are essential to monitor the healing progress, ensure the skin problem is resolving, and adjust treatment as needed.

It’s essential to follow your veterinarian’s instructions closely throughout the treatment process. In some cases, hot spots can be stubborn and may require extended treatment. Additionally, your veterinarian may recommend strategies to prevent future occurrences, such as environmental changes or dietary adjustments.

How to prevent hot spots in dogs

Sadly, not every problem that causes acute moist dermatitis in dogs can be prevented. However, there are several measures you can take that will help reduce the risk of your dog developing hot spots. 

Treating known underlying health issues and taking proactive measures to reduce the risk factors that contribute to this condition, you can spare your pup from the discomfort and pain. 

1. Grooming and hygiene:

Regular grooming practices are paramount in maintaining your dog’s skin health. Brush your dog’s coat regularly to remove dirt, debris, and loose hair, which can contribute to hot spots if left unattended. Pay special attention to long-haired breeds, as their coats are more prone to matting and moisture retention.

2. Drying after bathing or swimming:

After a bath or swimming, or after a walk in the rain, make sure the surface of the skin is thoroughly dried. Moisture trapped in the fur can create an environment conducive to hot spot development, especially in breeds with dense undercoats.

While all dog breeds can be affected by hot spots, some breed are a bit more predisposed because of their thick coat (for example Golden retrievers, German shepherds or Labrador retrievers_

3. Flea and tick control:

A major trigger for hot spots can be flea or tick infestations. To prevent these parasites, use effective flea and tick prevention products recommended by your veterinarian. Regularly inspect your dog for signs of infestation, especially in warmer seasons.

4. Allergen management:

If your dog has known allergic reactions, work with your veterinarian to manage and control these conditions. 

As you know by now, allergies can contribute to the development of hot spots, so minimizing exposure to allergens is key.

This might involve dietary changes in case of a food allergy, allergen-specific immunotherapy, or environmental adjustments.

5. Dietary considerations:

Feed your dog a balanced and high-quality diet that covers his nutritional needs. Proper nutrition is key for your dog’s  overall health and well-being. 

Omega-3 fatty acids and antioxidants are beneficial for the skin and coat, and your veterinarian can recommend specific dietary supplements if needed.

6. Behavior modification:

In some cases, hot spots can result from behavioral issues, such as anxiety or boredom. If your dog tends to excessively lick or scratch themselves, consult with a professional dog trainer or a veterinary behaviorist to address these underlying problems.

7. Environmental modifications:

Evaluate your dog’s living environment. Ensure your pet has a clean, dry, and comfortable place to rest. Remove any irritants or potential sources of moisture that could lead to hot spots. Maintain a consistent temperature and humidity level to avoid skin issues caused by extreme conditions.

8. Regular health checkups:

Schedule regular veterinary checkups to catch and address any skin issues or other health concerns early. Routine examinations help ensure your dog’s overall well-being.

9. Identifying and addressing underlying causes:

It’s crucial to identify and address any underlying causes that may predispose your dog to hot spots. 

These underlying causes could include allergies, skin infections, or irritants. 

Work closely with your veterinarian to determine the specific triggers for your dog and develop a targeted plan to manage or eliminate them.

10. Supervision and vigilance:

Watch your dog for signs of discomfort, itching, or any changes in their skin. Early detection and intervention can prevent hot spots from developing or becoming severe.

Remember that each dog is unique, and the preventive measures may vary based on factors such as breed, age, and preexisting health conditions. 

Consult with your veterinarian to create a tailored prevention plan that suits your pup’’s specific needs.

printable pet planner for busy dog owners

Hot spots are painful skin lesions that can progress in severe wound in a matter of hours. The best way to manage acute moist dermatitis is to take your dog to a vet and follow his recommendation. 

In very mild cases, you can try to treat your dog’s hot spot at home, but please consult any topical treatment with your vet. And it’s still good to know what caused the self-induced trauma in the first place, so you can prevent it from happening again. 

Remember that early detection, prompt treatment, and preventive measures are your greatest allies in keeping your dog’s skin healthy ☺️

Happy pet parenting ❣️

PS: If you are as crazy about animals as I am and want to get more pet health tips, subscribe to my newsletter! Today you will get a free pet planner as a bonus 

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