TLDR Minoxidil can cause allergic reactions, but testing helps identify the cause.
The article discusses cases of allergic contact dermatitis caused by the use of topical minoxidil preparations, which are used to treat male-pattern baldness. The reactions were predominantly caused by sensitization to minoxidil, but also to propylene glycol. The article recommends that dermatologists patch test patients to determine whether minoxidil or the vehicle is responsible for the reaction. The article also notes that topical minoxidil preparations have generally been well tolerated, except for some local irritation from the vehicle, and that the continuous use of a topical minoxidil preparation on the scalp reduces increased hair loss in male-pattern baldness and sometimes leads to the formation of new hairs.
29 citations,
August 1985 in “Contact Dermatitis” Minoxidil can cause allergic reactions like burning, itching, and red bumps.
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20 citations,
February 1985 in “Archives of Dermatology” Minoxidil helps hair regrowth, especially with more indeterminate hairs.
55 citations,
February 1985 in “Archives of Dermatology” Using minoxidil on the scalp can help grow hair for people with hereditary baldness.
80 citations,
September 1984 in “Journal of The American Academy of Dermatology” 5% minoxidil helps hair regrowth in androgenic alopecia.
95 citations,
December 1980 in “The New England Journal of Medicine” Minoxidil helped bald patient regrow hair.
17 citations,
May 1998 in “Contact Dermatitis” Minoxidil can cause pustular allergic reactions on skin.
14 citations,
July 1987 in “Contact Dermatitis” Minoxidil can cause allergic skin reactions in some users.
29 citations,
August 1985 in “Contact Dermatitis” Minoxidil can cause allergic reactions like burning, itching, and red bumps.
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