Itchy Armpits: Causes, Prevention, and Treatment

Common Causes

• Irritant/Allergic Contact Dermatitis: Deodorant/antiperspirant ingredients (fragrance, propylene glycol, aluminum, essential oils).
• Friction/Intertrigo: Skin-on-skin or fabric rubbing; moisture traps bacteria/yeast.
• Folliculitis: Shaving → inflamed hair follicles (S. aureus).
• Fungal Infection: Candida (satellite pustules), tinea (ringworm).
• Eczema (Atopic/Contact): Dry, fissured, lichenified.
• Psoriasis (Inverse): Smooth, red plaques in folds.
• Hidradenitis Suppurativa: Recurrent painful nodules, abscesses, sinus tracts.
• Systemic: Diabetes, thyroid disease, lymphoma (rare), medication reaction.

Prevention

• Keep clean and dry; pat thoroughly after shower.
• Fragrance-free, hypoallergenic deodorant (or none).
• Loose, breathable clothing (cotton).
• Shave with sharp razor, lubricant, with grain; or use trimmer/laser.
• Weight loss if intertrigo related to adiposity.

Treatment

• Topical hydrocortisone 1% (short-term) for inflammation.
• Antifungal (clotrimazole) if yeast.
• Antibacterial wash (chlorhexidine) or topical antibiotic (mupirocin) for folliculitis.
• Barrier: zinc oxide, petrolatum.
• Prescription topicals (calcineurin inhibitors, stronger steroids) for chronic eczema/psoriasis.

See a Doctor If

• No improvement in 1–2 weeks
• Spreading, pus, fever, red streaks
• Recurrent boils/abscesses (hidradenitis)
• Associated systemic symptoms