My Dog Has Crusty Scabs On His Back

There are several causes of crusty scabs on a dog’s skin.  You are probably concerned that there is a skin problem, allergies, bacterial infection, fungal infection or even ectoparasites. 

Crusty scabs on a dogs back
Crusty scabs on a dogs back

What If the Crusty Scabs Are Caused By Allergies?

Allergies can certainly be a cause of the crusty scabs on your dog’s back.  Your dog might have an environmental allergy to pollen, laundry detergents, shampoos, soaps, cleaning products and lawn chemicals.  Food allergies can also cause skin problems in some dogs.  If you know there has been a recent change in your dog’s environment or food, you may first try removing the change to see if the crusty scabs heal.  For example, if you washed your dog’s bedding in a new laundry detergent and the dog immediately thereafter developed the crusty scabs, try rewashing the bedding in your old detergent. If after removing the recent change, your dog still has crusty scabs on her back, a veterinarian may need to prescribe an anti-allergy drug along with steroids or have you apply an ointment or lotion on the affected areas.

What If the Crusty Scabs Are Caused By a Bacterial Infection?

Bacterial skin infection on a dog
Bacterial skin infection on a dog

 A bacterial infection called folliculitis may be the cause of the irritation, bumps, sores and scabs on your dog’s back.  This can be caused by allergies, psoriasis, fleas or injury. A bacterial infection may occur when your dog is continuously scratching his skin, breaking through the layers of skin creating cuts where bacteria gains entry, develops an infection and causes puss-filled sores and crusty scabs. Causes of the itching could be external parasites. 

  1. Fleas:  Check your dog for fleas.  Look for an area where your dog’s hair is thin; under the arms, the groan or belly, then examine the area for very small black insects.  A dog with fleas can obsessively lick, scratch and chew at the skin which can result in sores.  A flea infestation can cause blood loss, which can lead to anemia.   
  2. Mites:  Mites can cause mange in a dog.  It is a common skin problem in a dog that produces similar problems caused by fleas.  If the skin condition becomes severe, your dog’s hair may fall out and the skin will be covered with crusty scabs.
  3. Ticks:  Ticks are an insect that will partially embedded themselves into your dog’s skin.  Most dog owners can remove a tick themselves.  There are several devices on the market made especially for removing ticks.  If you do not have one of these on hand, use a pair of tweezers, position them as closely to the dog’s skin as possible, firmly grasp the tick and pull out of the skin.  Be sure you have also removed the tick’s head.  If the ticks heads remains embedded in the skin, it can lead to infection.    

Additional Causes of Crusty Scabs on a Dog’s Back

  1. Fungal infection: A fungal infection called ringworm can result in red, irritated skin, bumps, scaly skin, itchiness and hair loss.  Puppies under a year old are most prone to this kind of infection.  Ringworm gets its named because it appears as a circular, ring-like patch of irritated skin.  Your veterinarian will want to see the dog and will prescribe an ointment.
  2. Hormonal imbalance:  Your veterinarian can diagnose a hormone imbalance if it is the cause of your dog having crusty scabs on her back. 
  3. Auto-Immune Disorder:  Whenever a dog’s immune system becomes compromised it cannot fight skin irritants, or the dog’s own immune system may be working against itself.  This can also cause crusty scabs, but needs to be diagnosed by your veterinarian.
  4. Nutritional Deficit: Your dog may not be getting all the proper minerals and vitamins necessary and develops skin irritation, itchiness, and rashes that lead to sores and scabs on your dog’s skin.  Your veterinarian will prescribe a specifically, balanced diet that is formulated for your dog’s needs.  This food will keep the skin healthy, moisturized, and coat glossy.
  5. Yeast Infection:  This is a common kind of skin problem.  Yeast is normally present on the skin of a dog’s body.  Problems occur when the yeast population builds up in a warm, moist place and causes irritated, itchy, discolored skin.  A dog will chew, lick, and scratch the skin causing sores and scabs.  Your veterinarian will diagnose and prescribe a treatment
Yeast infection on a dogs skin
Yeast infection on a dogs skin

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