Hair Loss Medications

Currently, the only medications that are scientifically proven to be effective for hair loss treatment and approved by the US FDA are Finasteride (Propecia), potent prescription oral medication, and Minoxidil (Rogaine), a topical agent available without prescription.

The third medication, dutasteride (Avodart), is in clinical trials. It is similar to finasteride in action and has been approved in Europe for use in hair growth and is sometimes prescribed “off-label” for that purpose in the US. In the US dutasteride (Avodart) is licensed for treatment of benign prostatic hypertrophy (prostate enlargement) in men.

The vertex of the scalp is the area that is most likely to respond to treatment with medication.

Finasteride (Propecia)

Finasteride (Propecia) belongs to the classs of medications called type II 5-alpha reductase inhibitors. It is a prescription oral medication.

Finasteride slows the progression of hair loss and stimulates hair growth in parts of the scalp, where hairs are thin. Finasteride is unlikely to grow hair in areas that are completely bald.

In a large 5-year study4, 65% of men with mild to moderate alopecia had increases in hair count. And in nearly all men (90%) treated with finasteride (Propecia) for 5 years, the progression of hair loss was slowed.

How Finasteride (Propecia) works

Finasteride inhibits conversion of testosterone to dihydrotestosterone, causing dihydrotestosterone levels to decrease. Dihydrotestosterone (DHT) contributes to shortening of the growth phase of the hair and to hair thinning.

Problems and concerns

Treatment with finasteride (Propecia) may result in persistent sexual side-effects, including decreased libido (sex drive), erectile dysfunction, male breast enlargement.

Finasteride can be used only in men. The drug has not been proved effective in women and is not approved for women by the US FDA. Women who are or may become pregnant should not take or handle crushed or broken tablets, because finasteride can cause birth defects.

Finasteride (Propecia) is effective only for as long as it is taken. If you stop taking the drug, you are likely to lose the hair you have gained within 9 to 12 months. It is important to remember that when finasteride is discontinued, you only lose the hair that was gained by the medication, not more. As a result, you will return to the pretreatment level of balding.

Minoxidil (Rogaine)

Minoxidil (Rogaine) is a topical over-the-counter medication, available as 2% or 5% solution. Minoxidil is indicated for the treatment of hair loss (androgenetic alopecia) in both men and women, however the use of 5% solution is indicated for men only. The use of 5% minoxidil by women is contraindicated due to an increased risk of facial hair growth.

Minoxidil stimulates new hair growth and helps stop the loss of hair. The medication is moderately effective and when used correctly, 2% minoxidil has been shown to stimulate hair growth in about 30% of men, with a slightly higher rate in women3. Regrowth is more pronounced at the vertex than in the frontal areas and is not noted for at least 4 months.

How Minoxidil (Rogaine) works

The hair growth properties of minoxidil were an accidental discovery. Minoxidil was originally developed as a medication to lower blood pressure by vasodilation (dilating blood vessels).

How exactly minoxidil promotes hair regrowth is not well understood. Minoxidil appears to increase blood supply to the hair follicles, prolong the anagen phase of hair growth cycle, and increase hair follicle size2.

Problems and concerns

The main problem with this treatment is the need for continual regular application of the drug. If you stop using minoxidil, all regrown hair will gradually be lost, and the scalp will most likely get back to the pretreatment balding pattern.

Occasionally application of minoxidil can result in growth of unwanted hair on the face and other parts of the body.

Dutasteride (Avodart)

Ongoing studies are investigating the use of dutasteride (Avodart) in the treatment of hair loss in men1. Physicians in the U.S. sometimes prescribe Avodart “off-label” for treatment of male-pattern hair loss.

Dutasteride works in the same way as finasteride (Propecia) to reverse hair loss by inhibiting the convertion testosterone into dihydrotestosterone (DHT). However, unlike finasteride, this drug inhibits both type I and type II 5-a reductase isoenzymes. Studies show that dutasteride is superior to finasteride in treating androgenetic alopecia5, but it has yet to be approved by the FDA.

References

• 1. Stough D. Dutasteride improves male pattern hair loss in a randomized study in identical twins. J Cosmet Dermatol. 2007 Mar;6(1):9-13.
• 2. Messenger AG, Rundegren J. Minoxidil: mechanisms of action on hair growth. Br J Dermatol. 2004 Feb;150(2):186-94.
• 3. DeVillez RL, Jacobs JP, Szpunar CA, Warner ML. Androgenetic alopecia in the female. Treatment with 2% topical minoxidil solution. Arch Dermatol. 1994 Mar;130(3):303-7.
• 4. Finasteride Male Pattern Hair Loss Study Group. Long-term (5-year) multinational experience with finasteride 1 mg in the treatment of men with androgenetic alopecia. Eur J Dermatol. 2002 Jan-Feb;12(1):38-49.
• 5. Olsen EA, Hordinsky M, Whiting D, Stough D, Hobbs S, Ellis ML, Wilson T, Rittmaster RS; Dutasteride Alopecia Research Team. The importance of dual 5alpha-reductase inhibition in the treatment of male pattern hair loss: results of a randomized placebo-controlled study of dutasteride versus finasteride. J Am Acad Dermatol. 2006 Dec;55(6):1014-23

Written for HealthyStock.net, October 2009.