Minoxidil was invented in the 1950’s. It was initially a drug for hypertension sold under the trade name Loniten 1%. During the tests, before the drug was officially approved by The US Food and Drug Administration Agency, scientist discovered unexpected hair growth. The results of several studies indicated the possibility of the drug to be used in treatment of hair loss. In the 80’s Loniten became widely used as an off-label prescription for hair fall. In 1988, after years of consultations the FDA approved the medicine (under the trade name Rogaine) for treating baldness in men. Three years later the drug become also licensed for treatment of hair loss in women. Minoxidil became an over the counter drug in 1996, in 1997 a new 5% Rogaine formula was released and in 2014 it was the only FDA-approved topical drug for Androgenic Alopecia.
It is worth pointing out that the FDA concluded that Minoxidil was successful in only 39% of men with hair loss.
Minoxidil is available as 2%, 5% and 10 % foam or lotion. It is also sold in the form of cream which is stronger than the lotions or foams. Cream comes in concentrations of 12.5%, 15% and even up to 30% and is only accessible for men through prescription. 2% concentration is usually recommended for women who are experiencing hair thinning and hair loss. The medicine is not available on the NHS.
Minoxidil is applied topically. It is proved successful in men with Androgenic Alopecia where moderate or dense clinical hair growth is observed after 3 to 6 months of consistent daily use (twice a day for men and once a day for women). It is advisable to use Minoxidil indefinitely to maintain hair follicle nourishment and growth. Topical application of Minoxidil is considered to be a maintenance treatment therefore it should be used as long as hair is important to a patient. It’s been observed that efficacy of Minoxidil is slightly reduced after the period of 2 years of constant use.
There hasn’t been any conclusive evidence that Minoxidil is effective in patients with Alopecia Aerata.
Mechanism of minoxidil
The exact mechanism of Minoxidil is not known.
The enzyme called sulfotransferase converts topically applied minoxidil into an active chemical called minoxidil sulfate which then stimulates the hair follicle. Some medical studies have come to a conclusion that low activity levels of sulfotransferase in hair follicles might influence Minoxidil’s efficacy therefore only 40% of patients that use minoxidil experience hair growth. There may also be other biological factors like inflammation in the scalp which can affect the Minoxidil’s action.
Although minoxidil is usually well tolerated irritation of the eye, itching, redness or irritation at the treated area might appear. Unwanted hair growth elsewhere on the body may also occur as well as temporary hair loss. Severe allergic reactions including tingling or itching, hives, itching, eczema, swelling of the lips, face, tongue and throat or other parts of the body, wheezing, nasal congestion, dizziness, fainting, unexplained weight gain, trouble breathing have also been reported.
In some topical formulations alcohol and propylene glycol might cause dry scalp and consequently dandruff and contact dermatitis.