What are These Crusty Scabs & Bumps on My Dog’s Skin?

Skylar Dial
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Question: What are these scabs and bumps on my dog’s skin?


There are a couple of things that can be going on, and some of them may be innocent and not to be concerned about, but you should let your vet look at your dog to find out what is going on.

Bacterial Autoinoculation

This is where Bacteria can get into a scrape or even a cut, and then get into your dog’s bloodstream. It’s a potential problem with incisions or deep puncture wounds, and is a complication related to the surgery, and not caused by the surgery itself. You want to look out for slow healing, swelling and pus formation around the surgical sites (typically within the first 2-3 weeks, or longer). If any of these signs develop, do not hesitate to take your dog to the vet to look for a potential infection.

If the scab or bump is not healing at all, or is getting larger, could have a black center, or if there is any change in the lesion appearance, like forming a cauliflower like structure, or the surrounding skin is getting irritated or changes color, please don’t wait. The longer you wait, the more likely the wound gets infected and you run the risk of not being able to solve it.


After four years of being a pet parent, I just learned that I was handling my cat Pixie incorrectly. It’s strange that the way in which I pet my cat was actually causing irritation. And as a result, Pixie’s skin condition is actually my fault.

Shortly after bringing Pixie home, she developed a very itchy, scabby-looking skin condition. My vet was of no help. And I tried everything I could think of to get her hair back to a healthy and shiny condition. But my attempts had little effect. I’ve had cats and dogs in the past. And it’s one of those tedious pet parent duties that you learn to manage. And it’s also a duty that you do your best to provide relief for your pet.


Allergies in dogs cause a great deal of vulnerability to your dog. If you own a dog with allergies, then you need not worry anymore. Though the problem may seem terrible, there are ways to deal with it.

The most common allergy which affects a dog is as a result of its physical condition. They may suffer from allergies as a result of weight gain, old age and changes in their diet. If your dog has changed its diet recently or if it has gained too much weight, then the chances are that it may be allergic to the food it is being fed. A little bit of alteration in the diet can boost its energy levels and also prevent it from suffering from allergies.

Another common allergy is caused by flea bites. Allergic reactions in dogs as a result of flea bites can be treated by applying a small amount of calamine lotion to the bite. The topical application can successfully soothe your dog and can stop the itchiness that is associated with flea bites.

A common remedy for dog allergies is to bathe them in soapnut and rice bran oil. The bathing of dogs in soapnut and rice bran oil will heal the problem and will eventually solve the problem.

External parasites

Ticks are arthropods; they are arachnids (look like spiders) and insects (have six legs). They are about the size of a pinhead and can be brown, tan, or red. They have forceps-like structures called "hard" parts or "palps" on their heads. The palps are surrounded by hairs called "cerci". If you crush or squeeze the tick you will rupture the gut of the tick and digestive enzymes will be released, causing a pale sticky odor and irritating the skin of the host.

The most common indication of an adhered tick is usually an isolated bald area on the skin that may have a dark brown dot on the skin that is surrounded by a red halo. You may see these in areas such as in the armpit, groin, or on the inner thigh. This isn’t always the case, some ticks may burrow underneath the skin and cause an ill-defined circular tick bite. Sometimes these can take a while to notice so someone else may have to look for them. If one or several ticks are found, it is advisable to have the whole body of the dog checked.

Fungal Infection

My dog has developed small to large crusty sores usually on her back and tail. Many are bleeding when touched. She also has a large, red, crusty looking scab on her face that is very sore. I have used antiseptic ointment and cleaned the sores with mild peroxide. This has helped, except for the large scab on the face. Its size and appearance have not changed in the past two months. All sores/scabs are on her back or tail.

I have noticed that my dog has been scratching and biting her back and tail. But I have not noticed any fleas or ticks on her.

I am in the process of having her checked for heartworm. Can you tell me what else I should be checking into? What to look for?

Thank you for all your help!

The scabs/sores and crusty bumps my dog’s infected with are most likely caused by a fungal infection.

Fungal infections are very itchy and moist so your dog will be scratching and biting the infected areas. I would suggest you treat the wound with an antifungal ointment such as Miconazole, Gentian Violet or Clotrimazole. Also, to solve the issue, you should start treatment on the heartworm and treat her for ascarids and hookworms.

Diagnostic Testing of Dog’s Skin Bumps

Are you worried about the mysterious bumps or sores on your dog? They could be moles, skin tags, growths, injuries, or may even be the first signs of a cancerous tumor. You can take your pet to the veterinarian, but their approach will probably be based on the appearance of the skin bump, the hair loss, or other presenting symptoms.

If you have any concerns about your dog’s bumps and their potential medical implications, then you might want to consider having a vet or a veterinary dermatologist take a closer look before you make any decisions. However, it is also possible and much more affordable to do a test at home. Aside from the desire to rule out cancerous moles, these tests will also give you a good idea about other possibilities.


If you will be submitting samples to a veterinary hospital, it is important to know the difference between a biopsy and a sample submission. The former involves a surgical procedure where a piece of tissue is taken under sterile conditions and analyzed. Samples are submitted by swabbing the affected area. Your veterinarian may request minor surgery if there is an in-house clinic, while you may have to go to a local veterinary specialist for the surgery.

Diagnosis Leads to Better Treatment

Fading lumps and bumps on a dog's skin could indicate the presence of ectoparasites like fleas, ticks, or mites. This is extremely common and is often referred to as the "dirt dog" look. All dogs have the potential to be flea-infested because different variables including humidity, temperature, the type of coat, housekeeping habits, and other factors determine whether or not your dog will experience a significant issue with ectoparasites.

Here are some drug store remedies that may help to treat fleas, flea dirt and ticks and other ectoparasites.

[Understand what's happening on your dog's skin](./understanding-what-is-happening-on-your-dogs-skin)

[Learn how to stop flea infestation](./flea-treatment-for-dogs)

[Find out what ticks look like, where they hide on a dog's body and how to spot ticks in your pup](./infographic-what-to-look-for-if-he-has-ticks-on-his-skin)

[Learn how to diagnose mites](./understanding-the-dangerous-dangers-of-mites)