Bald Spots on Dogs: Top 8 Common Causes Explored

Author: K. Marie Altoby K Marie Alto Updated 8 min read

Bald Spots on Dogs: Top 8 Common Causes Explored

Recently, I wrote a whole post about bald patches on cats, and a few people have reached out to ask me: what about dogs? Our precious puppies have issues, too, so does the same advice apply, or are there differences between cats and dogs that need to be considered? So, of course, I'm writing a similar post for our canine companions.

If your fluffy doggo is having a hard time maintaining that fluff, there might be something wrong. So, let's talk about the causes, severity, and treatment of bald patches in our fur babies. While they can be dramatic, they have a lot of possible causes, and a range of different severities. So, while a bald patch is cause for some concern, you should hold off on the emergency trip to the vet E.R. until you're sure there's something worth the rush.

Are Dog Bald Spots Dangerous?

Before we dive into the specific causes for bald patches in dogs, let's address the elephant in the room: how dangerous are they? It's obviously distressing to see a patch of that lustrous fur coat disappear, or to be brushing your pooch and have much larger clumps of fur than normal come away with each stroke. How bad is it?

The answer here depends on the cause of the issue. Unfortunately, it's never a simple answer, because there are many different reasons why your fur baby might be losing some of their fur. Fortunately, mostof the time you don't need an emergency appointment, and when you do, there are usually other more concerning symptoms – like difficulty breathing – that warrant the trip.

Are Dog Bald Spots Dangerous Image by Toe Beans

My recommendation is this:

  • Check for serious symptoms that might make an ER trip a good idea.
  • If no symptoms exist, call your vet and explain the situation.
  • Your vet will ask you questions, which can help you determine whether you need an urgent appointment or a normal appointment.
  • At your vet's recommendation, do any home treatments that may help in the meantime.

Bald patches can turn into lesions, sores, and infections if they're left untreated, and they can return if you don't know the cause and address it. Plus, they're often pretty uncomfortable, not to mention unsightly. While your pooch may be just as happy as ever despite the spot, deep down, they may not be comfortable, and we don't want that.

What Are the Causes of Bald Spots on Dogs?

As with cats, there are a variety of different possible causes that can lead to bald spots. Many of the causes are the same, but there are a few differences we'll talk about as well.

Causes of Bald Spots on Dogs Image by Toe Beans

To determine what the issue is, your vet will ask you about symptoms and probably run some tests. They'll look for where the hair loss is, how big and how it's shaped, and can inspect the area with a trained eye. As for tests, they can check a blood panel, a biopsy if there's a suspicion of a tumor, and skin smears that can show bacteria or other infections. If nothing else comes up, you may have to go through an elimination diet to check for allergens in food.


One of the most common reasons why a dog ends up with bald spots is allergies. Dogs can have allergies or sensitivities to things like mold, dust mites, pollen, household chemicals, and even foods. While allergies present differently, especially depending on how the allergen is exposed, bald spots are not uncommon.

Basically, it works in pretty much the same way as dermatitis does in humans. Your dog either brushes up against something that they're allergic to, or they eat it, and it causes a flood of histamines in the affected area. This leads to inflammation and a whole bunch of symptoms, including itching, scratching, biting and nibbling, sneezing, irritated and watery eyes, eye discharge, runny nose, and, of course, bald patches.

Allergic reactions are also part of the other causes of bald patches, as well. I'll mention those when we get to them.

A Dog With an Allergy Image by Toe Beans

So, how bad is an allergic reaction? Well, just like in people, it can range from a minor and temporary irritation all the way up to an emergency situation. A person who is allergic to peanuts, for example, might get itchy and red when exposed, or they might break out in hives and run a fever, or they might go into anaphylactic shock. The same can happen with dogs; it can be a minor irritation, a significant problem, or a life-threatening ailment.

Fortunately, if the main symptom you're seeing is hair loss, it's probably not immediately life-threatening. Most allergens, if they're in the system long enough to cause hair loss, are a low-level, long-term kind of reaction. If it's life-threatening, it's going to be abrupt and cause respiratory problems first and foremost.

Parasites or Infections

Pretty much any nasty little gribbly that gets into or onto your fur baby can cause bald spots. Infestations – like fleas, ticks, ringworms, mites, or other kinds of parasites – occur because they bite or live in or on the skin. The skin, of course, doesn't like that and reacts with inflammation, irritation, and other symptoms.

Flea infestations are honestly one of the most common causes of bald spots on dogs, especially when those spots show up in areas like around the collar and behind the ears, where fleas can hang out without the dog getting at them.

The most extreme cases of this are things like mange, which is a type of mite infestation that can go wildly out of control, especially in stray dogs or dogs that get lost for an extended period.

Infections, meanwhile, are similar but inside the dog. Things like worms, skin infections, or bacterial infections can all present with a variety of symptoms, including hair loss. This is often more general, but a localized infection – like if your dog ran through a thornbush, got scraped, and had a cut that got infected – will have more localized bald spots.

A Dog With a Tick Image by Toe Beans

Generally, with these kinds of issues, you want to look for other symptoms. Things like mites, fleas, and ticks are all pretty obvious. Other infections might have characteristic looks, like roundworms. Also, keep an eye out for things like thickened skin, itching, oily skin, or circular patches of hair loss.

All of these are pretty well treatable. You're generally going to need your vet to identify what the infection is and give you the appropriate treatment, which might be antibiotics, antifungals, antiparasitics, or something else. You'll also likely be given something like a soothing cream or a medicated shampoo to use, and in some cases, steroids to help with the inflammation. It's rare that anything but the most unchecked, antibiotic-resistant infection is dangerous, at least.

Pressure Sores

Another relatively common cause for bald spots is pressure. In humans, we get bedsores and pressure ulcers. Dogs, with their fur coats, have that insulative layer to take the brunt of the pressure first.

Basically, pressure and friction rub at the fur and skin, and that damages the fur and skin over time. The more pressure and friction, and the longer it happens, the more damage builds up. Eventually, it can wear away enough at the fur to cause a bald spot, and eventually can start to cause skin irritation, and even scarring or calluses over time.

This is most common in large, heavy dogs and in older dogs. It's also characteristic of places where your dog's skin contacts some object. It's usually in elbows, hips, and other joints. It can also happen with dogs that have very low activity levels.

A Dog With Pressure Sores Image by Toe Beans

There are a few ways you can handle this issue. An orthopedic bed can reduce pressure and friction if your dog finds it comfortable enough to use. You can also use baby clothing and bandages to cover the areas that are seeing hair loss, allowing the fur to regrow because the fabric takes the friction instead. In some dogs, you might use compression sleeves as well.

It's also a good idea to get your pooch moving from time to time, so they get up and aren't laying in one position for hours at a time. Of course, for elderly dogs, you might just want to let them sleep. Either way, this isn't a terribly dangerous cause for bald spots unless it's starting to cause ulcers and infections, and you generally won't let it get that far, right?

Cushing's Disease

Hair growth is governed by hormones, and one of those hormones – the stress hormone cortisol, also known as adrenaline – can cause hair loss when it's present in excessive amounts. This is why people and animals lose hair when they're stressed.

Cushing's Disease is the name for hyperadrenocorticism, which is when your dog's hormonal system goes wild and produces too much cortisol. This can be caused by anything from age to a tumor on some part of the hormonal system and is most common in older dogs.

A Dog With Cushing's Disease Image by Toe Beans

Other symptoms of Cushing's Disease include increased thirst and hunger, frequent urination, panting, thin skin, lethargy, reduced activity, a pot-belly appearance, and a higher chance of skin infections.

How bad is it? Moderate. Cushing's Disease is manageable with medication, and in the case of something like a tumor, it may be treatable with surgery. However, it's something that you're going to have to actively manage and pay attention to for the rest of their life.


Cushing's Disease is when the body produces too much cortisol, but it's not the onlyreason why the body might produce more cortisol than normal. Stress, ranging from a major move or rearranging of the house to a bad encounter with another dog to general anxiety, can all lead to increased cortisol levels. This can, in turn, lead to hair loss. Unfortunately, this is often delayed – it takes time for the hormones to affect the hair follicles and longer for those hair follicles to grow out or die off – so the actual stressful event may have been weeks or months in the past. Fortunately, as long as the stress is temporary, so is the hair loss.

A Stressed Dog Image by Toe Beans

Boredom can also cause hair loss in some cases. Separation anxiety, boredom causing excess grooming, and other issues can all relate.

Genetic Hair Loss

Just like how we people – men, mostly – lose hair as they get older, so too can dogs. Genetics can play a role in hair loss, and it's not always graceful. It is, however, generally related to breed and age. Dogs like Dachshunds, Chihuahuas, Whippets, and Greyhounds can end up with patchy hair loss when they hit around 1-2 years old; other breeds lose hair as they get into their final years.

Genetic Hair Loss Image by Toe Beans

There's nothing you can really do about genetic hair loss, but you still might want to check with your vet to make sure it's not a different problem.

Other Causes

There are a few other potential causes for bald patches. An injury, especially one that scars over, can leave a bald patch behind. Post-surgical healing can do it, too. Cancer can wreak havoc on your fur baby's system, too, and cause hair loss both from having weird bulges from tumors and from disrupting hormones.

All of these have different levels of severity and different kinds of treatments. As usual, talk to your vet at your next appointment.

A Dog Healing From Surgery Image by Toe Beans

Have you ever had to deal with a dog with bald patches or spots? What did it turn out to be, and how did you fix it? We never like to imagine our poor fur babies suffering, so it's always helpful to share the signs and symptoms with fellow pet parents so we can all be prepared.

Fortunately, at least, most of these causes are pretty minor and easily treatable. Whether it's a simple prescription medication, a medicated shampoo, a changed diet, or a fancy outfit, dogs can adapt to anything, and we can keep our fur babies happy and healthy as long as possible. So, tell me your story below!

K Marie Alto
K Marie Alto

K. Marie is an animal lover, wife, kitty mom, dog auntie, writer, and co-founder of Toe Beans, a proud American family-owned online boutique pet supplies store focused on the improvement of the life of furry family members via pet parent education, better products, and advocacy. She has over 20 years of experience as a pet momma. She loves sharing her personal journey and experience as a pet parent via her blog and Facebook page where she currently has more than 50K followers (@furrytoebeans) and counting :-). Read more

Leave a comment

Comments will be approved before showing up.

Also in Pet Parents Blog by Toe Beans

10 Common Questions and Answers About Puppy Biting
10 Common Questions and Answers About Puppy Biting

by K Marie Alto April 18, 2024 8 min read

Explore common questions about puppy biting and learn why puppies nibble, how to address this behavior, and if it's possible to train puppies to stop biting.
Cat Paw Anatomy: A Closer Look at Paw Structure
Cat Paw Anatomy: A Closer Look at Paw Structure

by K Marie Alto April 10, 2024 8 min read

Explore the intricate anatomy of your feline friend's paws, from the sweat glands in their toe beans to the structure of their claws and the number of toes.
The Ultimate Guide: Teaching 20 Essential Dog Commands
The Ultimate Guide: Teaching 20 Essential Dog Commands

by K Marie Alto April 04, 2024 8 min read

In this guide, we'll share 20 of the best commands you can teach your dog, ranging from simple commands like come or sit to more complex ones like sit pretty.