TLDR Minoxidil didn't increase scalp blood flow for hair growth, but hexyl nicotinate did.
In a study conducted 36 years ago, researchers investigated the effect of 3% minoxidil and 0.1% hexyl nicotinate on scalp blood flow in ten male subjects with androgenic alopecia. The study aimed to explore the mechanism behind minoxidil's ability to promote hair regrowth, hypothesizing that it might be due to increased scalp blood flow. Using Laser Doppler Velocimetry, the researchers found that 3% minoxidil did not increase scalp blood flow in any of the subjects, while 0.1% hexyl nicotinate did lead to an increase in all but one subject. The onset of the effect of hexyl nicotinate was around 7 minutes, with the effect lasting for an average of 52 minutes. These findings suggest that vasodilation may not be the mechanism by which minoxidil promotes hair growth in the treatment of alopecia, indicating that further research is needed to understand the drug's properties and its relationship with hair growth.
138 citations,
August 1985 in “Journal of The American Academy of Dermatology” Minoxidil promotes hair growth in male pattern baldness.
55 citations,
February 1985 in “Archives of Dermatology” Minoxidil applied twice daily can help regrow hair in some people with hereditary baldness, with no serious side effects.
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80 citations,
September 1984 in “Journal of The American Academy of Dermatology” 5% minoxidil helps hair regrowth in androgenic alopecia.
137 citations,
May 1984 in “Journal of Investigative Dermatology” Minoxidil increases blood flow in balding scalps, possibly reversing hair loss.
16 citations,
April 1984 in “Archives of Dermatology” Topical minoxidil can help hair regrowth in alopecia areata patients, but maintaining the growth after stopping treatment is inconsistent.
80 citations,
October 1983 in “BMJ” Minoxidil helps hair regrowth in alopecia patients, with 16 having good results and no side effects.
[object Object] 73 citations,
November 1979 in “British Journal of Dermatology” Minoxidil can cause excessive hair growth.
August 2022 in “Contact dermatitis” Severe allergic reactions to hair dye can trigger hair loss and may be linked to multiple sclerosis.
14 citations,
January 2015 in “Skin appendage disorders” Minoxidil treatment for hair loss can cause scalp allergy and severe hair loss.
The woman has unexplained hair loss and it's unclear what her condition is or how to treat it.
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7 citations,
January 2009 in “International Journal of Trichology” Dermoscopy can't help doctors identify scalp irritation caused by topical minoxidil.
54 citations,
March 1987 in “Journal of The American Academy of Dermatology” 3% topical minoxidil effectively treats extensive alopecia areata with few side effects.
