Minoxidil is currently produced under both the trade name of Rogaine Topical Solution and various other names. The medication's exact mechanism of action is unknown. We know it stimulates the hair follicles' active growth (the anagen phase), causing the hairs to thicken and grow longer. Minoxidil is helpful in slowing down the rate of hair loss in approximately 70%-75% of patients, and about one in two patients actually experiences hair re-growth.

Minoxidil topical solution is available over-the-counter (without a prescription) in both 2% and 5% concentrations. To be effective, the solution should be applied to the scalp once or twice daily.

The new 5% Rogaine Foam is aimed at those who complained about the solutions being messy.

Side effects are uncommon, occurring in approximately 2% of patients. They are mostly dermatological: skin itching, scaling and redness. Many of these cases can use a propylene glycol free minoxidil solution which may alleviate these symptoms.

2% minoxidil is the only medical therapy approved for women.