Folliculitis in Dogs

Mixed race veterinarian examining dog in hospital
Jose Luis Pelaez Inc / Getty Images

Folliculitis is a skin condition that commonly affects dogs. Irritation of a hair follicle causes inflammation in the area, leading to swelling, redness, itchiness, pain, and other skin lesions. Ic can have a variety of causes, all of which require veterinary treatment.

What Is Folliculitis in Dogs?

Folliculitis is a term used to describe the inflammation of a hair follicle that is typically related to a bacterial infection. Hair follicles are tiny openings in the skin through which hair grows. One or more of the follicles gets irritated or infected, causing the area to become red and swollen. Folliculitis in dogs is often first presented as red bumps on the skin that may be filled with pus.

Signs of Folliculitis in Dogs

  • Redness
  • Swelling
  • Itching
  • Papules
  • Pustules
  • Alopecia
  • Epidermal collarettes
  • Pain in affected areas
  • Hyperpigmentation

Dogs with folliculitis will have one or more skin lesions on the body. It may start as a small raised area on the skin that looks like acne (called a papule). The area may become more raised and fill with pus (called a pustule). Folliculitis may cause itching, pain, and hair loss (alopecia) that has a patchy or moth-eaten appearance (but can also be widespread on the skin). Some dogs develop crusty/flaky round skin lesions called epidermal collarettes. Hyperpigmentation (dark spots on the skin) may also occur in some areas of the skin.

Causes of Folliculitis in Dogs

Folliculitis in dogs occurs when one or more of the hair follicles becomes damaged or irritated. It is usually caused by some kind of infection.

Folliculitis is most commonly caused by an infection of Staphylococcus bacteria, but it can be caused by other types of bacteria. Other potential causes of folliculitis in dogs include viral or fungal infections, parasites, trauma, and systemic diseases.

Certain skin problems can make a dog more susceptible to folliculitis. Although there are no dog breeds genetically predisposed to folliculitis, dogs prone to allergies are also at a greater risk of developing folliculitis.

Diagnosing Folliculitis in Dogs

It's best to first contact your veterinarian if you think that your dog has folliculitis or another skin condition. After getting information from you about your dog's signs and history, your vet will do a physical examination. Your vet may be able to diagnose folliculitis on the exam, but further testing is sometimes necessary to determine the cause. Potential testing includes the following:

  • Skin cytology to look at the cells under a microscope
  • Skin scrape to check for parasites like mites
  • Skin biopsy, where tiny samples of the skin are removed surgically and sent to a pathologist for detailed analysis
  • Fungal or bacterial cultures
  • Blood work and urinalysis to assess organ function and blood cell counts.

Treatment for Folliculitis in Dogs

The treatment of folliculitis in dogs is determined by the cause. Therapy typically involves a combination of systemic medications and topical applications like sprays, creams, ointments, and shampoos.

Topical treatments are used in most cases to ease discomfort and reduce inflammation. Your vet may recommend regular baths with a medicated shampoo. Sprays, creams, or ointments containing steroids, antibiotics, or antifungal agents are often necessary as well.

Bacterial folliculitis is usually treated with oral antibiotics. A long course of treatment may be necessary to eradicate the bacteria. Fungal folliculitis requires antifungal medications. Certain types of fungal infections require long-term treatment.

Parasitic infections require medication to kill the parasites as well as supportive care to promote healing. Antibiotics may still be prescribed to treat a secondary infection. If the folliculitis was caused by a systemic disease, then that disease must be treated first. Antibiotics may still be necessary in case of a secondary infection. Depending on the disease, long-term or lifelong treatments may be necessary.

How to Prevent Folliculitis in Dogs

Folliculitis in dogs cannot always be prevented. Early detection and treatment is the best way to keep folliculitis from getting worse. Be sure to contact your veterinarian for advice at the first sign of skin problems.

Dog owners can take steps to prevent folliculitis in dogs by keeping other skin issues under control. Be sure that you contact your veterinarian at the first sign of skin issues. If your dog is currently being treated for any health problems, be sure to continue all treatments as recommended by your veterinarian.