Regaine is a topical solution for treating male baldness with an active ingredient called Minoxidil. Usual concentrations are 2% and 5%. Minoxidil can help re-grow of hair by improving circulation to the scalp. The usual dosage is topical application to the affected area twice daily.  Side-effects include irritant contact dermatitis and allergy. People may have different response to this medication. According to research findings, about 33% of users will have cosmetically acceptable hair re-grow after 12 months of continuous usage of 2% Minoxidil. However, baldness may recur after stopping.  

If you have any questions, please consult your family doctor.