What Causes Hot Spots in Dogs?

Have you ever noticed your dog spending a bit more time scratching than usual? We all suffer from an occasional itch here and there, but if your pup seems to have a nagging skin irritation that appears to be out of the ordinary, it could be an early indicator of a dog hot spot.

But exactly what is a hot spot in dogs? Acute moist dermatitis, commonly known as hot spots, is an inflammation of your dog’s skin that can sometimes lead to more serious bacterial infections if left untreated. Read our blog on How to Identify an Infected Hot Spot on Dogs to learn more about infections.

Not sure if you’re missing the signs of a hot spot on your dog? Keep reading to find out what to look for, how to determine their underlying causes, and what the best treatment plan might look like for your pet. 

Many small insects like flies, ants, and mosquitoes are apt to bite pets when they’re playing outside at the park or running along a wooded trail. Because of this, dog owners might not think much of it if they come home and notice a red spot or two on their pup’s belly or limbs.

How can you tell the difference between a hot spot and a harmless insect bite?

Start by keeping an eye on your dog’s behavior. Is there excessive licking or itching in a particular area? If your dog suddenly starts acting uncharacteristically aggressive, this too could suggest that they’re experiencing discomfort as a result of hot spots.

Next, you’ll want to do a closer examination of the area that seems to be the source of irritation. Here are a few things you’ll want to look for if you’re concerned about hot spots:

• Strong/foul odor
• Pus or discharge
• Blood
• Redness
• Matted patches of fur
• Crusty or open sores
• Dry skin that is flaky or scaly
• Hair loss in localized areas of the body

Make note of the symptoms that your dog is experiencing at home and stay vigilant to be sure they do not become progressively worse. If they do not improve within a few days, it may be time to book an appointment at your local veterinarian clinic. 

What causes hot spots on dogs? Though it can often be the result of a particularly irritating insect bite, acute moist dermatitis can cause itchiness, pain, or swelling in your pet for several other reasons, too.

Have a look over this list of common causes to determine what might be triggering your dog’s symptoms. 

Sometimes, because of the very nature of their breed, certain dogs are more susceptible to hot spots than others. Does your dog have long, thick hair? Allowing the skin to breathe properly can be challenging when layers of fur lock in moisture and dirt.

Long-haired dogs such as huskies, golden retrievers, Saint Bernards, or collies are among the breeds most prone to hot spots.¹

Do you ever notice that your skin seems to be extra finicky in the summer season? In warm weather months, people may experience higher amounts of rashes and dermatological irritation often due to the higher production of sweat and extra time spent swimming in pools, lakes, and oceans.

The same is true for dogs.

Cooling your pup down with a dip in your local swimming hole is important, but so is toweling them off afterward to be sure they’re not sitting in a damp coat for the remainder of the day. Built-up moisture and sweat may increase your pet’s chances of developing painful hot spots. 

Fleas are sometimes unavoidable, but some dogs are especially sensitive to this biting pest. If your dog is improperly groomed, poor hygiene can cause the occasional flea to multiply, resulting in a highly itchy infestation. If you think your dog may be hypersensitive to a flea bite, consult with your vet to find the best way to stop them before they start. 

Whether it’s an external parasite like ticks or mites, or an internal parasite that has somehow found its way into your dog's intestines, external skin irritation, like hot spots, might be a sign of a larger, underlying problem. Your vet can perform external examinations or order a blood test to see if a parasitic infection is what’s causing your pet’s discomfort. 

If you notice your pup scratching away incessantly at their ears or neck, this could be an indication of an ear infection. The reason ear infections can be linked to hot spots is because of the constant scratching caused by bacteria in the ear canal. One problem can quickly snowball into two if, by scratching to provide relief from an ear infection, they irritate the surrounding area enough to cause a hot spot flare-up. 

Just like humans, dogs can have allergies to food and their environment. If your pup has a food allergy, it may manifest as nausea, vomiting, diarrhea, or swelling. In other cases, the allergic reaction can cause intense itching, which often leads to hot spots in dogs. Talk with your vet to see if a pre-existing allergy is what’s behind your dog’s acute moist dermatitis. 

Does your dog have separation anxiety? How many hours a day does your dog spend at home with little to no stimulation? Dogs that are stressed or bored may take to licking or scratching as a coping mechanism. Too much of this can create a breeding ground for hot spots to emerge and worsen. 

Knowing the reason behind your dog’s bout with acute moist dermatitis is an essential part of prevention. Once you know what’s causing the problem, you can take steps toward improving your dog’s overall health to make sure hot spots are never an issue for you or your furry friend.

Is your dog getting regular exercise? Do they have good hygiene?

Keep careful watch and utilize these preventative measures:

• Perform regular skin checks
• Talk with your vet about finding the appropriate flea treatment for your dog
• Dry them off completely after swims and baths
• Schedule regular grooming appointments
• Add a medicated shampoo to the shelf if you know your dog may be more prone to hot spots
• Avoid boredom by taking your dog out for regular walks or increasing their playtime at home
• Stay informed about your pet’s food allergies and ensure that their diet is not causing any adverse reactions
• Trim your dog’s coat during the summer months, particularly in susceptible breeds
• Monitor your pet for excessive licking or scratching

Hot spots are not uncommon and are usually easy to treat. If you’re already familiar with how to recognize hot spots and can catch them before they take a turn for the worse, it’s possible to treat them right at home without having to pay a visit to your vet.

Here’s how you may be able to heal hot spots at home:

• If you have the proper grooming tools, and you and your pet are both comfortable with it, you may decide to shave around the affected area to keep it clear of any further irritants. Moist, matted hair can cause mildly irritating hot spots to turn into large lesions that can become swollen or bleed. If you’re inexperienced or you know your dog can sometimes put up a fuss, leave this part of the treatment to your vet.
• Clean the area with a gentle antiseptic or use an antimicrobial hot spot spray to minimize your pet’s discomfort and lower the possibility of infection.
• Apply cold compresses a few times daily to soothe the affected area and consider having your pet wear a cone to prevent licking and itching.

If your dog’s hot spots have developed into open sores that sometimes bleed or produce pus, you should contact your veterinarian and schedule an appointment as soon as possible. A professional examination will help to identify or rule out any resulting bacterial infections that may have occurred. After shaving the hot spot area, the vet will prescribe the best treatment for your dog’s particular case.

Some vets may prescribe:

• Nonsteroidal anti-inflammatory drugs (NSAIDs) like carprofen or deracoxib to help with swelling²
• Medicated wipes to be used daily to keep the area clean
• Topical or oral antibiotics in cases of severe bacterial infections

The duration of the healing process will vary depending on the severity of your pet’s condition and the type of treatment prescribed. By sticking to a cleaning schedule and keeping your dog from irritating or reopening a wound, most hot spot cases show signs of improvement after just a few days. In other cases, treatment for resulting bacterial infections may take up to six or eight weeks.³

Sources: 

1. Clinician’s Brief. Acute Moist Dermatitis. https://www.cliniciansbrief.com/article/acute-moist-dermatitis
2. WebMD. 6 Most Common Dog Health Problems. https://pets.webmd.com/dogs/6-most-common-dog-health-problems#1
3. PetMD. Sarcoptic Mange in Dogs. https://www.petmd.com/dog/conditions/skin/c_dg_sarcoptic_mange

Noticing similar symptoms in your cat? At Vetericyn, we are here to help you understand what causes hot spots in cats, as well as the best treatments for cat hot spots.