Medically reviewed by Susan Bard, MD Some causes of underarm rash include infection, allergic reaction, and inflammation. Itchy, inflammatory, bacterial, or fungal rashes in your armpit can be mild or ...

Medically reviewed by Casey Gallagher, MD Armpit rashes often develop due to allergic reactions, infections, and chronic conditions. Rashes are common under the arms because the skinfold creates a ...

Other causes of an armpit rash include a yeast infection, psoriasis, or seborrheic dermatitis. Rashes are pesky patches of irritated skin that can affect any part of your body, including your armpits.