Pet Care Resources Hot Spots in Dogs: What They Are and How to Treat Them

Dermatology

Hot Spots in Dogs: What They Are and How to Treat Them

If your dog has an acute onset of a patch of red, inflamed itchy skin caused by severe scratching at a body site, they may have created a “hot spot.” This skin condition is termed pyotraumatic dermatitis, or acute moist dermatitis, and often affects the neck, base of the ear, rump, or area of the trunk. Hot spots require emergent care to stop the itch and prevent further self-trauma. Your pet may need additional treatment if there is a secondary bacterial infection. If this problem recurs often, your dog may benefit from a consultation with a veterinary dermatologist to definitively treat and identify the underlying cause. 

What Are Hot Spots? 

Pyotraumatic dermatitis is the acute onset of a self-induced localized skin lesion initiated by rapid increase of a bacteria (usually Staphylococcus pseudintermedius) on the skin surface which is worsened by self-trauma to the area.  

The bacteria grow in an area of inflammation, moisture, matted fur, or other. The pet starts maniacally biting or scratching at the affected part of the body. Your pet may develop a patch of hair loss, red skin, and seeping fluid from erosion in the skin. It initially involves the skin surface but may progress to involve the hair follicle and become a pyotraumatic folliculitis, an inflammation and likely infection of the hair follicle. If there is a folliculitis, the lesion will have an irregular bumpy surface (papules), often identified when clipping the hair coat around the lesion. 

Dog breeds with thick, heavy, dense hair coats are more likely to develop hot spots. Examples include the Golden and Labrador Retriever, Collie, German Shepherd, Saint Bernard, Akita, and Newfoundland. Swimming, chronically wet fabric collars, or tightly fitting electric fence collars can increase risk. Hot and humid environments can also make pets more likely to develop hot spots due to trapped heat or humidity at the skin surface where the bacteria reside. The change in the microenvironment encourages bacteria growth.  

Other causes of hot spots that may initiate or be a trigger for recurrent episodes include: 

  • Ectoparasites (fleas) 
  • Allergic skin disease including cutaneous adverse food reaction (a.k.a. food allergy) 
  • Atopic dermatitis (a.k.a. environmental allergies to pollen, mold, dust mites, or other) 
  • Ear infections 
  • Reactions to topical substances 
  • Poorly kept or moist hair coats (from swimming or bathing) 
  • Arthritis 

How Are Hot Spots Diagnosed?

Diagnosis of pyotraumatic dermatitis is based on history of an acute onset of signs, dermatologic examination, and the results of in-house diagnostic tests such as skin surface cytology to look for bacteria (or other) and skin scrapings (to look for follicular or surface-dwelling parasites).  

How Are Hot Spots Treated?

The first step to treatment involves removing the grouping of bacteria from the skin surface. The affected area will be clipped and thoroughly cleaned, usually with a chlorhexidine scrub.  

Your veterinarian will prescribe something for itch and inflammation. This may be an oral anti-inflammatory medication like prednisone for a short period of time or Apoquel. They will also prescribe something topical for the lesion. This may include a drying agent, such as 2% aluminum acetate, or a 1% hydrocortisone with aluminum acetate solution applied topically two to three times a day until the lesion is healed. If folliculitis is present, treatment will include systemic antibiotic therapy.  

Your pet may get an Elizabethan collar (also known as a cone) to keep from licking or scratching the area while it heals.  

How Can Hot Spots Be Prevented?

In general, careful attention to grooming, bathing, flea control, and ear cleaning can help avoid hot spots from developing on your dog.  

If your pet’s hot spots are triggered by an underlying issue such as allergic skin disease, your veterinarian can guide you on the best plan. They may recommend additional exploration of the cause and suggest that you consult a veterinary dermatologist. 

By Lauren Pinchbeck, DVM, MS, Diplomate, ACVD |
July 24, 2023