Minoxidil works by enlarging the diameter of the hair follicle, causing a thicker hair, and by prolonging the anagen stage of hair growth which results in longer and a higher number of hair strands. essentially it slows the replication process. According to "Fitzpatrick's Dermatology in General Medicine," studies have shown that "up to 60 percent of men show improvement in vertex balding...with a mean increase in hair density of 10 percent to 12 percent."
I am going to speculate here.
If the hair follicles on your face have the same receptors that Minoxidil targets then yes, it would help you grow that hair. I could see higher results in the chin area than anywhere else on you face. Everyone will be different based on their genetics.
Hope this helps.
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