minoksidol

Minoxidil, sometimes transliterated as minoksidol in non-English sources, is a vasodilator drug used topically to treat androgenetic alopecia and hair thinning. It originated as an oral antihypertensive medication and was later developed into a topical formulation for hair growth.

The exact mechanism by which minoxidil promotes hair growth is not fully understood. It is thought to widen scalp blood vessels, increasing blood flow to hair follicles and stimulating follicular activity. It may promote the transition of hair follicles from the resting phase to the growth phase and enlarge miniaturized follicles, leading to thicker-looking hair for some users.

Topical preparations are available as solutions (commonly 2% and 5%) and as a foam. The typical regimen is to apply to the dry scalp over the affected areas twice daily, with care to avoid contact with eyes or other sensitive areas. Hands should be washed after application. Results, when they occur, are generally seen after 4 to 6 months of consistent use, and ongoing treatment is usually required to maintain any benefit.

Effectiveness varies among individuals. Minoxidil is not a cure for hair loss and is more beneficial for some people, particularly those with recent onset of androgenetic alopecia. It may slow hair loss and promote regrowth in a subset of users.

Safety and adverse effects include local irritation, itching, and dermatitis. Unwanted hair growth can occur on the face or other areas if the product contacts non-target skin. Rare systemic absorption can cause dizziness or tachycardia. Oral minoxidil, in contrast, has more significant risks such as fluid retention and tachycardia and is prescribed for hypertension rather than hair loss.

Topical minoxidil is OTC in many countries; oral minoxidil requires a prescription. Brand names commonly associated with topical formulations include Rogaine or Regaine.