TLDR Minoxidil, when applied to the scalp, can stimulate hair growth but effects vary, stop if treatment ends, and it may cause side effects like fluid retention.
In 2007, a study was conducted to examine the effects of topically applied Minoxidil, a drug originally used for hypertension, on baldness. The study involved daily applications of 1%, 3%, or 5% Minoxidil to the scalps of patients with male pattern baldness. Results showed evidence of hair growth stimulation, although it was delayed and varied among patients. Long-term studies of 6-12 months showed hair growth ranging from minimal to significant restoration. However, hair growth stopped when Minoxidil therapy was discontinued. The study also found that Minoxidil was poorly absorbed through the skin, with less than 4% of the applied doses recovered from the urine. Side effects included fluid retention and hypertrichosis. The study concluded that more research was needed to assess the potential of topical Minoxidil as a hair growth stimulant in patients with alopecia areata and alopecia androgenetica.
80 citations,
October 1983 in “BMJ” Minoxidil helps hair regrowth in alopecia patients, with 16 having good results and no side effects.
56 citations,
August 1981 in “Journal of The American Academy of Dermatology” Minoxidil helps hair regrowth in alopecia areata safely.
95 citations,
December 1980 in “The New England Journal of Medicine” Minoxidil helped bald patient regrow hair.
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57 citations,
January 1980 in “Journal of Cardiovascular Pharmacology” Minoxidil treats high blood pressure and side effects can be managed.
73 citations,
November 1979 in “British Journal of Dermatology” Minoxidil can cause excessive hair growth.
46 citations,
April 1977 in “Southern Medical Journal” Minoxidil causes excessive hair growth, but depilatory agent removes it safely and effectively.
31 citations,
August 1975 in “Journal of Pharmaceutical Sciences” Minoxidil metabolizes similarly in monkeys and humans, but differently in dogs and rats.
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90 citations,
May 1972 in “Clinical Pharmacology & Therapeutics” Minoxidil quickly leaves blood, turns into urine metabolites, and has lasting blood pressure-lowering effects.
53 citations,
February 2020 in “Expert Opinion on Pharmacotherapy” Finasteride and minoxidil work best together for hair loss.
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35 citations,
March 2005 in “Journal of Investigative Dermatology” Potassium channel openers like minoxidil help hair grow by acting on hair follicles.
2 citations,
June 2011 in “Expert Review of Dermatology” Female pattern hair loss involves thinning hair on crown and frontal scalp, diagnosed by hair ratio, and treated with minoxidil, antiandrogens, or hair transplantation.
5 citations,
February 2011 in “Expert Opinion on Drug Discovery” We need better treatments for hair loss, and while test-tube methods are helpful, they can't fully replace animal tests for evaluating new hair growth treatments.
3 citations,
January 2015 in “Social Science Research Network” The conclusion is that off-label drug use can lead to important medical discoveries and improve patient care.
118 citations,
April 1998 in “Dermatologic Clinics” Finasteride and minoxidil are effective for hair regrowth, while treatments for alopecia areata have varying success and continuous treatment is necessary.
