Underarm Itchiness: Causes, Relief & When to See a Doctor

* Skin irritation: Tight clothing, shaving, or using deodorant can irritate the skin under your armpits and cause itching.

* Sweat: Sweat can cause the skin under your armpits to become damp and irritated, which can lead to itching.

* Bacteria: The bacteria that live on your skin can multiply in the warm, moist environment under your armpits and cause itching.

* Allergies: You may be allergic to something in your deodorant, soap, or other products that come into contact with your underarms.

* Medical conditions: Certain medical conditions, such as eczema, psoriasis, and diabetes, can cause itchy armpits.