Low-dose oral minoxidil as treatment for non-scarring alopecia: a systematic review

Background Topical minoxidil has been used for almost 40 years to treat alopecia. There is growing evidence supporting off-label use of low-dose oral minoxidil. Objective To conduct a systematic review evaluating the use of oral minoxidil for all types of alopecia. Methods A primary literature search was conducted using PubMed in May 2019, utilizing the search term "oral minoxidil AND (hair loss OR alopecia OR baldness)". Reviews, non-English studies, and articles concerning only topical minoxidil were excluded. Results Ten articles were included for review comprising a total 19,218 patients (215 women and 19,003 men). Oral minoxidil dose ranged from 0.25 to 5 mg daily to twice daily. The strongest evidence existed for androgenetic alopecia and alopecia areata (AA), with 61-100% and 18-82.4% of patients demonstrating objective clinical improvement. Successful treatment of female pattern hair loss, chronic telogen effluvium, monilethrix, and permanent chemotherapy-induced alopecia was also reported. The most common adverse effects with oral minoxidil included hypertrichosis and postural hypotension. Conclusion Oral minoxidil is a safe and successful treatment of androgenic alopecia and AA. In addition to its therapeutic benefits, practical advantages over topical minoxidil stem from improved patient compliance.