Inverse psoriasis (also known as intertriginous [in-ter-TRIJ-uh-nus] psoriasis) appears on skin of color as lesions of purple-ish, brown, or darker than the surrounding skin, in body folds. On Caucasian skin, it appears as bright red lesions in body folds. It may appear smooth and shiny. Many people with inverse psoriasis have another type of psoriasis elsewhere on the body at the same time.

Symptoms

Inverse psoriasis is found in the armpits, groin (including the genitals), under the breasts, and in other skin folds on the body. Rubbing and sweating can further irritate inverse psoriasis because of its location in skin folds and tender areas. It usually lacks the scale associated with plaque psoriasis due to the moist environment. Inverse psoriasis is more common in overweight people and those with deep skin folds.

Psoriasis on the skin folds is considered a high-impact site, which can have an increased negative impact on quality of life, regardless of the total area affected by psoriasis.

Triggers

Common triggers for inverse psoriasis include:

• Certain medicines
• Starting and stopping medicines
• Infections
• Injury to the skin
• Stress
• Tobacco or alcohol use
• Friction on deep skin folds

Treatments

Treatment options typically include topical treatments or systemic medications for more severe inverse psoriasis.

Because skin folds can be prone to yeast and fungal infections, your health care provider may prescribe a combination of treatments. Do not occlude (cover) skin folds unless directed by a health care provider. To keep the lesions in skin folds dry and to lower the risk of fungal infection, your provider may recommend the use of powders to dry the moist lesions.

You and your health care provider will discuss the best treatment plan for you based on the nature and severity of your symptoms, and your medical history.

Last updated on 2/8/2024 by the National Psoriasis Foundation.