Trichomycosis is a bacterial infection that can develop in underarm and pubic hair. While some cases resolve on their own, others require treatment with topical antibiotics.

Trichomycosis, also referred to as trichomycosis axillaris or trichobacteriosis, is a bacterial infection of the underarm hairs. In rare cases, this infection can also affect pubic hair. Trichomycosis is not life-threatening, but it can cause some irritation and discomfort.

Trichomycosis typically produces no symptoms and can be easily missed. However, there are a few signs you can look for:

This condition is not contagious. However, you should seek treatment once you notice symptoms. Trichomycosis can affect multiple areas at the same time. If you think your symptoms are getting worse, contact your doctor.

This bacterial infection affects people of all ages, ethnicities, and genders. However, women are less likely to have this infection because they tend to shave under their arms.

Other risk factors for developing trichomycosis are:

Your doctor will conduct a physical exam to diagnose your condition. During the exam, they’ll look at your hair and nodules on the hair shaft.

There are also two tests used to differentiate trichomycosis from lice: Wood’s lamp exam and microscopy.

Wood’s lamp exam

Your doctor may use a handheld Wood’s lamp to examine the affected area. This lamp uses a black light to show bacteria shining a different color. This procedure can help to differentiate between different bacterial infections and diagnose trichomycosis.


A microscopic exam is a procedure that involves testing samples of tissue or other matter under a microscope. Your doctor will look for foreign bacteria, yeast, and other irregularities.

Trichomycosis is treatable. The infection can clear up within a few weeks with proper management and good hygiene. Before applying any treatment method, you should shave the hair in the affected area.


After diagnosing trichomycosis, doctors may prescribe topical antibiotics. Your doctor may prescribe clindamycin or erythromycin lotion. Apply these creams to the affected area twice a day for up to two weeks.

You may also receive benzoyl peroxide gel or lotion. These ointments may cause skin irritation.

If the topical antibiotics do not work, your doctor could prescribe an erythromycin pill. You should take these supplements daily for up to two weeks.

If symptoms do not clear up, talk to your doctor about getting more tests and different treatment recommendations.

Healthy hygiene

Proper hygiene can help to eliminate bacteria from the affected areas. This includes:

  • washing the area every day with soap and water
  • using antiperspirant to reduce sweating and bacterial buildup
  • using talc-free drying powders like baby powder or Gold Bond to help reduce moisture
  • thoroughly washing and drying your clothes after wearing them

You should be able to stop your trichomycosis from coming back if you follow good hygiene and keep your underarms clean and dry. Use antiperspirant daily and after washing to reduce excess moisture and the collection of bacteria. Using antibacterial soap can also help to eliminate bacteria.