Men’s Rogaine’s Active Ingredient: Minoxidil Men’s Rogaine contains minoxidil, which revitalizes hair follicles, likely causing them to shift from a dormant phase to an active growing phase. Scientists believe that minoxidil works by aiding the blood flow to the hair follicles in your scalp, thereby helping hair regrowth. How to Use Apply half a capful (equivalent to 1g of foam) 2 times a day to the scalp in the hair loss area. Massage into scalp with fingers, then wash hands well. Using more or more often will not improve results. Continued use is necessary to increase and keep your hair regrowth or hair loss will begin again.