Dark thighs and underarms

Skin folds rub during walking, exercise, or close-fitting clothing. Heat and moisture can trigger intertrigo, while shaving, waxing, deodorants, or fragranced products may irritate the surface. After irritation settles, post-inflammatory hyperpigmentation can remain even when the skin no longer feels sore. Thick, velvety skin or darkening in several folds deserves a clinical examination because pigment alone does not identify the cause.

Keep folds dry, choose breathable clothing, and wash without harsh scrubbing. Pause products that sting and use a bland moisturiser on irritated skin. Do not apply lemon, bleach, or strong acids at home. A clinician may discuss [Chemical Peel](/treatments/aesthetic-procedures/chemical-peel/), [Laser Hair Removal](/treatments/laser-and-energy/laser-hair-removal/), [Laser Toning](/treatments/laser-and-energy/laser-toning/), or [Hydroquinone Treatment](/treatments/medical-dermatology/topical-hydroquinone-therapy/) only after identifying the trigger.

Book an assessment when darkening persists, spreads, becomes thick or velvety, or returns after each episode of irritation. Seek prompt care for pain, open cracks, foul odour, pus, marked redness, or fever, which can signal active inflammation or infection.

Ask what is driving the pigment, whether fold inflammation is present, which hair-removal method is least irritating for your skin, and whether a prescription treatment should be used before any cosmetic procedure.