Dandruff Treatment

Dandruff is driven by an overgrowth of Malassezia yeast — a normal skin resident — combined with an individual sensitivity to the oils it feeds on. This triggers faster skin turnover on the scalp, producing the visible flakes. It is not caused by poor hygiene and is not contagious; genetics, stress, cold or dry weather, hormonal shifts, and skin conditions like seborrheic dermatitis all influence how often it flares.

Effective OTC options include zinc pyrithione, selenium sulfide, ketoconazole 1%, coal tar, and salicylic acid — each targets a different aspect of the process. Use a medicated shampoo 2–3 times per week, leave it on the scalp (not just the hair) for 3–5 minutes before rinsing, and alternate between two different actives if one loses effect over time. Regular use is what maintains control; stopping usually leads to flares within weeks.

Consider prescription care if OTC shampoos haven't controlled symptoms after 4–6 weeks, if the scalp is red, sore, or has thick well-defined plaques, or if the flaking spreads to the eyebrows, ears, beard, chest, or nasal folds. Options include ketoconazole 2% shampoo, ciclopirox, topical corticosteroid lotions or foams for inflamed patches, and — for widespread seborrheic dermatitis — short courses of topical calcineurin inhibitors.

Dandruff is a mild form of seborrheic dermatitis limited to the scalp; more inflammatory or widespread cases (redness, greasy yellow scales on the face, ears, or chest) are called seborrheic dermatitis. Scalp psoriasis looks different — thicker silvery scales, well-defined plaques that may extend past the hairline, and often less oiliness. A clinical exam distinguishes them and guides treatment, since the medications overlap but aren't identical.

Medicated shampoos can cause dryness, scalp irritation, or occasional hair discoloration — selenium sulfide and coal tar are the most likely culprits, and coal tar can stain light-colored hair. Ketoconazole and ciclopirox are generally very well tolerated. Topical steroids used long-term on the scalp can thin the skin and cause folliculitis; they should be used in short courses to calm flares, not as ongoing maintenance.