A sudden crusty scab on a dog can throw any owner into full panic mode. But most skin problems are pretty common and easily treatable.

But why do crusty scabs start to develop on your dog’s back? It could be due to allergies, cuts, fleas, or even a bad scratching habit. If you’re not 100% sure what’s the cause, the best you could do is visit a vet. 

Let’s learn more on the topic:

What Are Crusty Scabs?    

A crusty scab is a protective layer of tissue that forms over damaged skin. It’s made of proteins, skin cells, collagen, and red and white blood cells. That acts as a natural band-aid, preventing more blood from flowing out. Also, a scab keeps the germs out of the cut, allowing the skin cells underneath to heal.

But what does a scab look like on a dog? Scabs come in different shapes and sizes, and they look like raised formations on your dog’s skin. They’re typically dark red or brown but may darken more with time. After the wound heals, the scab dries up and falls off.

A crusty scab is usually a positive indicator of the healing process. But if it’s not a result of a physical injury, you should find out what’s causing it and start treatment as soon as possible.

Most Commonly Affected Body Parts

Crusty scabs can appear pretty much anywhere on the dog’s body. Still, you can usually spot them on the back and neck areas. They can also occur on the belly and upper legs, since the creases of a dog’s skin can cause irritation.        

Dogs at Risk       

Crusty dog skin conditions aren’t linked to a specific breed. But if your dog is overweight, has excess skin, or has big floppy ears, its scabs may heal slowly. Also, older dogs may have difficulty recovering from crusty scabs due to their aged, dehydrated, and coarser skin. If your dog suffers from such conditions, consider switching to dog food for sensitive skin.

Causes of Crusty Scabs on a Dog’s Back

The first step is figuring out the cause of a crusty scab on your dog’s back. That way, you’ll avoid treating only the symptoms and solve the actual problem. 

So, if you’re wondering, “Why does my dog have scabs?” here are some of the most common causes:

Food Allergies

Although food allergies are less common, dogs can still get them. For instance, they’re typically allergic to the protein found in chicken, beef, dairy products, and eggs. But they can also be allergic to wheat. In any case, a home pet allergy test may come in handy. 

If your dog scratches itself to the point of causing scabs, that’s a clear sign that it may be dealing with an allergy. Food allergies can cause scabs on a dog’s head, feet, and around the anus. Other common symptoms are:

  • Dry skin
  • Red skin
  • Increased bowel movement
  • Vomiting

Pollen Allergies

Pollen is among the most common allergy triggers. If it comes into direct contact with your dog’s skin or your dog inhales the pollen from the air, the allergy kicks in. That leads to allergic dermatitis, causing:

  • Itchiness
  • Sores
  • Rashes
  • Skin irritation
  • Redness
  • Dog allergy scabs

The allergy usually causes the most discomfort to dogs in spring, summer, and fall.

If you notice that your dog is allergic to pollen, the best you could do is visit a vet.

Stray dog skin disease.

Environmental Allergies

Environmental factors are the most common cause of dog allergies. They cause an overreaction to something from the dog’s surroundings. That could be:

  • Washing detergents 
  • Shampoos
  • Soap
  • Dust
  • Cleaning products
  • Lawn chemicals 

Just about anything in your dog’s surroundings can result in skin irritation if your dog’s allergic to it.  

Signs of environmental allergies usually begin to show in young dogs between 1–3 years. Since that’s genetic, some breeds, like Golden Retrievers, Bulldogs, and Labrador Retrievers, are more prone to it.


Ticks are parasites that stick to the skin and feed on a dog’s blood. A tick scab on dog skin can appear if you didn’t pull the tick gently, or some of the skin got ripped during the removal. 

Besides scabs, ticks can also cause irritations, itchiness, and sores. The good news is that you can easily spot them on your dog’s skin and remove them with tweezers.

Be careful because the head can sometimes remain inside your dog, leading to infection. It’s essential to keep your dog free from ticks since they can transmit diseases to humans.


All dog owners are familiar with these pests, but did you know that dog scabs from fleas are also a thing? Although they might be hard to spot, fleas are among the most common causes of skin allergies in dogs.

These external parasites feed on the dog’s blood. Some pups are allergic to flea saliva, causing them to lick, scratch, and obsessively chew their skin. That leads to hot spots and can even result in flea scabs on dogs.

So, you should know how to get rid of flea eggs. You should first use an anti-flea shampoo and a comb to remove as many eggs as possible. Other great options include:

  • Concentrated IGR (Insect growth regulator) sprays
  • Oral flea treatments
  • Collar-based treatments


Like ticks and fleas, mites are common parasites that cause skin disorders called mange in dogs. There are two types of mange:

  • Demodectic mange — Demodex mites that cause Demodectic mange aren’t visible with a naked eye. They usually affect young dogs and aren’t that itchy. Still, they can cause hair loss, bald spots, and sores. Demodectic mange isn’t contagious.
  • Sarcoptic mange — Scabies mites can also affect dogs, resulting in Sarcoptic mange. Although it’s not that common, they’re contagious to other animals and humans. Sarcoptic mange leads to severe itching, red skin, sores, your dog losing hair in patches, and scabs. Since this type can infect humans, too, you should be careful when treating your dog. 

Yeast Infection

Did you know that yeast infection can also affect dogs? It’s pretty standard. A type of fungus called Malassezia that lives on dogs’ skin can cause a yeast infection if the immune system is compromised.

These infections develop in moist places like:

  • Paws
  • Armpits
  • Skin folds
  • Ears

So, if your dog has dry, flaky skin and scabs, musty odor, and hair loss, a yeast infection is likely. Other symptoms include:

  • Itching
  • Redness
  • Scratching
  • Head shaking
  • Darkened or thickened skin

Bacterial Infection

Bacterial skin infections usually occur due to a skin disorder, allergies, or injury. They develop due to the dog’s constant scratching, licking, and biting on its inflamed skin, creating cuts where bacteria can enter. That can cause a dog paw infection that may also lead to a crusty bump on dog skin. The condition is treatable with antibiotics.

Fungal Infection

Although fungal infections sound a bit scary, they’re not that big of a deal. They’re common skin conditions that can lead to hair loss, bumps, and itchiness.

Ringworm is among the most typical fungal infections in dogs. They can find this fungus in the soil or through another infected dog.

Also known as dermatophytosis, ringworm appears as a red, circular, ring-like patch of irritated skin. So, if you notice these characteristic red spots on dog skin, take some extra care because the fungus can easily pass between people and dogs. Puppies under one year are especially vulnerable because their immune system isn’t that strong.

Nutritional Deficiency

Believe it or not, a poor diet can seriously affect a dog’s skin. Well-balanced, high-quality meals are the key to its tip-top shape. That will ensure healthy, moisturized, and good-looking skin.

Some skin problems can develop if your dog isn’t getting all the necessary vitamins and minerals. Lack of proper nutrition can cause skin irritations, itchiness, and rashes, leading to dry skin scabs on the dog’s back. 

After ruling out other causes, it’s possible that your pet’s diet doesn’t provide the nutrients it needs. A veterinarian can help you figure out the deficiencies and restore nutrition to the optimal level.   

Hormonal Imbalance

Hormonal problems can also affect dogs. Common causes include endocrine system inefficiencies or hormonal abnormalities in the dog’s adrenal glands, pituitary glands, testicles, or ovaries.

Such imbalances can lead to hair loss, causing skin irritation and scabs on dogs. Although this is among the most serious causes of crusty scabs, you can treat it if caught on time. If you don’t, the scabs can indicate tumor growth, Cushing’s disease, or hypothyroidism


If your puppy looks like entering its teen years, struggling with pimples, you might be dealing with an impetigo condition. 

It’s a skin infection due to the bacteria Staphylococcus that primarily affects puppies. The infection typically affects their soft bellies, armpits, and groins. Although impetigo isn’t contagious and can resolve itself, appropriate treatment can speed up the recovery process and prevent spreading.

Due to its itchiness, impetigo is rather uncomfortable for dogs. Characteristic signs of the condition are pimple-like lesions and a red rash on the dog belly. These red bumps contain a white substance called pus (pustules) and can break, forming crusts. 

Seborrheic Dermatitis

Dogs can also suffer from Seborrhea. It develops when the skin produces too much sebum, leading to excessive greasiness.

If your dog has dry, flaky skin and scabs, an unusual smell, and itchiness, Seborrhea might be the cause. It usually affects the back, but it can also occur on the face and skin folds.

The condition is inheritable and typically occurs in breeds like Basset Hounds, Cocker Spaniels, and Dachshunds. It can also be a secondary disease. Secondary Seborrhea is more common and often related with:

  • Obesity
  • Fungal infections
  • Poor diet
  • Allergies
  • Parasites
  • Hormonal imbalances

Autoimmune Disorder

It occurs when your dog’s immune system attacks its own cells by mistake, resulting in serious diseases. Although rare, it has many forms. Some common autoimmune skin diseases in dogs are Canine Lupus and Pemphigus.

This potentially life-threatening condition can also cause skin lesions on dogs and crusty scabs. Autoimmune diseases in dogs are rarely curable. But with proper medications, you can at least control them.

Hot Spots

Hot spots are red, inflamed, moist skin areas that can spread pretty easily. They’re usually caused by excessive licking, chewing, and scratching due to bacterial infections, allergies, or insect bites.

It’s easier to prevent hot spots than to cure them. So, if you own a water-loving pup, make sure to dry it after swimming or being in the rain.

Pet check-up routine

How to Check Your Pet for Crusty Scabs

Finding a crusty scab on dog skin isn’t hard since the scabbed areas are often rougher. But having a long-haired dog can make that a bit more challenging. In this case, you’ll need to push the hair back to reveal the scab. If you’re not sure whether you saw a tick or a scab, just remember that ticks stick out, while scabs are typically flat against the skin.

Visiting a vet is always the best way to unravel your dog’s crusty skin problem. They’ll perform all the necessary examinations and help you determine the cause.


Treating dog skin scabs won’t be easy if you don’t know the reason behind them. Still, there are some essential tips you can follow to prevent scabs on your dog’s skin:


A well-balanced diet is the first step in protecting your dog from crusty scabs.

A poor diet can cause dry and itchy skin, often leading to a crusty raised scab on dog skin. Plus, it affects your pet’s overall health.

Feeding your dog high-quality nutritional food will provide all the necessary minerals and vitamins. So, it’s essential to figure out the optimal nutrition for your furry friend.

Fish Oil Supplement

Fish oil supplements are good for the skin and coat, and they can help prevent an itchy scab on dog skin.

Since your pet might not get the necessary Omega 3 fatty acids from its diet, it’s always a good idea to include them through supplements. Nordic Naturals omega-3 pet gels on Amazon is an excellent option to keep your dog’s skin in peak condition.

Skin Balms

Skin balms are another effective way to prevent crusty scabs on dog. They can help your dog heal easily from them by reducing inflammation and the scratching urge. 

In addition to nourishing the skin, a pawsome Forticept antimicrobial gel on Amazon will significantly ease your dog’s discomfort. By disinfecting wounds and preventing skin infections, it creates an optimal environment for healing. Plus, it’s alcohol-free.

Flea and Tick Meds and Collars

Small scabs on dog skin can form due to flea and tick bites. Although it’s essential to treat them, it’s always better to address the cause first.

Topical and oral treatments will keep fleas and ticks off of your dog. But make sure to ask your vet for advice before using meds.

Another simple solution to prevent fleas and ticks is to get a collar. YiXiEr collar for dogs on Amazon offers safe, eco-friendly, and long-lasting protection. It’s a waterproof collar that will keep your dog free from fleas and ticks for up to a year.

Anti-bacterial and Anti-Fungal Shampoos

An ideal home remedy for preventing scabs is anti-bacterial and anti-fungal shampoos. If your furry pal suffers from a bacterial or fungal infection, resulting in dog skin infection, scabs and itching, these shampoos can help. Regular use can relieve your pet from discomfort and keep diseases in check.

Anti-bacterial and anti-septic, Veterinary Formula medicated dog shampoo on Amazon is the perfect choice for treating skin problems. It promotes silky fur and will quickly become your all-time favorite.


Antihistamines work well for symptoms of skin allergies in dogs. For dog scab treatment, it’s best to use:

  • Clemastine — It’s one of the most effective meds for itchy skin but a more expensive option.
  • Hydroxyzine — Besides treating itchy skin, it’s also useful for allergic reactions to flea bites, stings, and vaccines. Also, it comes in small pills, so it’s easier for dogs to swallow it. Possible side effects are vomiting, diarrhea, dry mouth, and lethargy. So, before you rush to buy it, make sure to check with your vet first.

Hygiene Tips for Your Pet and Home

Let’s take a look at some additional hygiene tips for your pet and home:

Regular Brushing and Bathing       

Regular brushing keeps your dog’s skin and fur healthy. It removes dirt, flaky patches, foreign objects, and parasites that can cause sores on dogs.

Brushing your dog’s coat stimulates oil production and distributes the dog’s natural oils equally. It detangles the coat, eliminates dead hair, and relieves itchiness. Five to ten minutes of brushing a day will do the job, but your furry pal might be up for even more.

Unlike daily brushing, you should bathe your dog monthly or more frequently if necessary. Always make sure to use a quality dog shampoo that won’t irritate the skin.

Cleaning Your Dog’s Toys and Bedding

Although keeping your dog clean is essential for avoiding crusty sores on dogs, it’s equally important to wash its toys and bedding. That will keep fleas and germs away. 

We recommend washing your dog’s bedding and toys with a pet-safe detergent at least once a week.

House Cleaning

A clean environment is crucial for your dog’s skin and overall health.

To eliminate nasty bacteria and parasites that cause dog skin problems, you should regularly vacuum carpets, sweep, and mop the floors. Pay extra attention to places where your dogs like to sleep and lay around.

Final Thoughts

Skin problems are among the most common reasons for a vet visit. While discovering a crusty scab on dog skin can be scary, most of the time, that’s just a result of a healing injury.

Causes of scabs can vary from allergies and parasites to more severe conditions like hormonal imbalance or an autoimmune disorder. If the problem persists, contact your vet as soon as possible. They’ll help you find the cause, set the treatment, and make optimal diet recommendations. Treating the root of the problem is always the first step.

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