TLDR Minoxidil causes excessive hair growth in almost all patients.
This article describes a case of hypertrichosis (excessive hair growth) in a patient taking the hypotensive drug minoxidil. The article reviews the literature and suggests that hypertrichosis is a common side effect of minoxidil, occurring in nearly all patients treated with the drug. The mechanism behind this side effect is unknown, but it is thought to be related to increased cutaneous blood flow. The article also notes other side effects of minoxidil, including cardiotoxicity, fluid retention, tachycardia, nausea, fatigue, dyspnea, pigmentation, coarsening of facial features, and gynecomastia.
102 citations,
September 1977 in “The Lancet” Minoxidil with propranolol and diuretics lowers blood pressure but causes fluid retention and hair growth.
86 citations,
September 1977 in “BMJ” Minoxidil effectively controls blood pressure in severe cases, but has serious side effects and causes hair growth in women.
46 citations,
April 1977 in “Southern Medical Journal” Minoxidil causes excessive hair growth, but depilatory agent removes it safely and effectively.
7 citations,
January 2021 in “Cureus” A woman had an allergic skin reaction to a hair loss treatment containing minoxidil and should not use it.
4 citations,
January 2017 in “Indian Dermatology Online Journal” A child used a hair growth lotion for hair loss, but it caused excessive hair growth on his face and neck instead.
10 citations,
February 2016 in “Anais Brasileiros de Dermatologia” Topical minoxidil can cause excessive hair growth in children, so use it carefully.
5 citations,
March 2013 in “Journal of cosmetic and laser therapy” Laser treatment successfully removed unwanted facial hair caused by minoxidil.
20 citations,
March 1994 in “Clinical and Experimental Dermatology” Too much topical minoxidil can cause excessive hair growth, but stopping treatment reverses it.
24 citations,
February 1987 in “Drugs” Minoxidil promotes hair regrowth, but more research needed for effectiveness and response factors.
73 citations,
November 1979 in “British Journal of Dermatology” Minoxidil can cause excessive hair growth.