Minoxidil is a drug that is used for treating male-pattern baldness. Oral minoxidil was originally used for treating high blood pressure, but patients and health care providers noticed that hair growth was a side effect of treatment. This led to the development of topical (solution applied to the skin) minoxidil for the treatment of male-pattern baldness. The mechanism of action leading to growth of hair is unknown.
Minoxidil (trade names Rogaine, Regaine, Avacor, Loniten (orally), and Mintopamong others) is an antihypertensive vasodilator medication which also slows or stops hair loss and promotes hair regrowth.
Minoxidil was first used exclusively as an oral drug (trade name Loniten) to treat high blood pressure. However, it was discovered to have an interesting side-effect: Minoxidil may cause increased growth or darkening of fine body hairs, or in some cases, significant hair growth. When the medication is discontinued, the hair loss will return to normal rate within 30 to 60 days. Upjohn Corporation produced a topicalsolution that contained 2% minoxidil to be used to treat baldness and hair loss, under the brand name Rogaine in the United States and Canada, and Regaine in Europe and the Asia-Pacific. Treatments usually include a 5% concentration solution that is designed for men, whereas the 2% concentration solutions are designed for women. The patent on minoxidil expired on February 11, 1996.
In 2007 a new foam-based formulation of 5% minoxidil was claimed to be as effective as the liquid-based treatment for male pattern baldness.
DOSINGMinoxidil should be applied as 1 ml of solution or half a capful of foam to dry hair and scalp once in the morning and again in the evening. It should be spread evenly over the affected areas, and then the hands should be washed with warm water (if the hands are used for application). Minoxidil must be applied on the scalp at least twice daily and for at least four months to see results. Minoxidil works less well in patients that are older, have larger areas of baldness, and have been bald for longer periods of time. Minoxidil should be applied to a dry scalp only, and left in place for at least four hours. Minoxidil must be continued in order to maintain or increase the hair growth achieved.
Minoxidil should not be used with other topical medications because they may increase its absorption and side effects. Minoxidil should not be used in pregnancy. Minoxidil should not be used by nursing women because it has not been evaluated adequately in nursing mothers.
USING MINOXDIL WITH DEXPANTHENOL
The mechanism by which minoxidil promotes hair growth is not fully understood. Minoxidil contains the nitric oxide chemical moiety and may act as a nitric oxide agonist. Similarly, Minoxidil is a potassium channel opener, causing hyperpolarization of cell membranes. Minoxidil is less effective when there is a large area of hair loss. In addition, its effectiveness has largely been demonstrated in younger men (18 to 41 years of age). Minoxidil use is indicated for central (vertex), or top of head, balding only.
Minoxidil is also a vasodilator. It is speculated that by widening blood vessels and opening potassium channels, it allows more oxygen, blood, and nutrients to the follicle. This can also cause follicles in the telogen phase to shed, usually soon to be replaced by new, thicker hairs (in a new anagen phase).
SIDE EFFECTSAdverse reactions include irritation of the skin, itching,contact dermatitis, and dryness of the scalp or flaking. An increase in the absorption of minoxidil from the scalp can occur in patients with damaged skin, leading to increased side effects. Minoxidil's contains alcohol that can irritate the eyes. In case of accidental contact with eyes or other sensitive areas, the exposed area should be washed with cool water.
Alcohol present in topical preparations may dry the scalp, resulting in dandruff. Side effects of oral minoxidil may include swelling of the face and extremities, rapid and irregular heartbeat, lightheadedness, cardiac lesions, and focal necrosis of the papillary muscle and subendocardial areas of the left ventricle. There have been cases of allergic reactions to minoxidil or the non-active ingredient propylene glycol, which is found in some forms of topical Rogaine.