Two percent (2%) topical Minoxidil, the only FDA-approved agent for female
pattern hair loss treatment, showed efficacy over placebo in many trials.
- Investigator global assessment determined – through a well-designed
32-week study – that the application of 2% Minoxidil twice-daily
stimulated mild to moderate re-growth in 63% of 157 women treated with
Minoxidil compared
to 39% of 151 women treated with vehicle.
- Non-vellus hair counts on
the top of the scalp of 256 women aged 15 to 45 years suffering Ludwig
I or II alopecia treated with 2% topical Minoxidil
showed a mean increase of 14 percent over baseline compared with 7.3 percent
for those on placebo. Results were taken from a 32-week trial period.
- To assess the efficacy and safety of 2% topical Minoxidil solution
for the treatment of pattern baldness in women, 10 European centers
conducted
a 32-week, double-blind, placebo-controlled trial; results led to the
conclusion that topical Minoxidil solution was significantly more effective
than placebo
in the treatment of pattern baldness in women. The mean increase
in the non-vellus hair count in the 2% percent Minoxidil group was 33
hairs,
significantly greater than that of 19 hairs in the placebo group. Investigators
saw 44 percent new growth of those treated with topical Minoxidil and
only 29 percent of those on placebo.
The outcome on women with hyperandrogenism may not be as positive however.
FDA-controlled studies on women showed no evidence of increased effectiveness
of the 5% solution. No significant difference in scalp coverage could be
appreciated by investigator global assessment in a 48-week, well-designed
comparative efficacy study of the 5% versus the 2% topical Minoxidil in
the treatment of mild to moderate female pattern hair loss. Patient satisfaction
with the use of the higher concentration, however, was appreciably greater.
Using higher concentration in women showed modest benefit at best, and its
use should only be considered in those cases that show minimal response
to the 2 percent formulation; as shown by subsequent studies.
Studies using hair counts as a primary endpoint in the evaluation of female
pattern hair loss have shown a mean increase in hair growth of 15-33% in
the Minoxidil-treated goops compared to the 9-14% increase in the vehicle
groups. On the other hand, a one small study using hair weights as the endpoint
found an increase of 42.5% in hair weights in the Minoxidil group compared
to the 1.9% in the control group. Minoxidil was superior over the vehicle
in the investigator and subject assessments. However, 40 percent of the
subjects appeared not to respond to Minoxidil. It’s also important
to note that none of these trials were extended over 32 weeks, and the long-term
results of Minoxidil treatment are uncertain. The beneficial effects on
hair growth on men are lost rapidly on cessation of treatment and it is
most likely that the same effect will hold true in the case of women.
Dosage and application of Minoxidil on female pattern hair loss
Effective dose of Minoxidil solution is one milliliter (25 drops) – must
be used twice daily applied directly onto a dry scalp and then slightly
spread with the fingers. Regardless of the extent of the affected area,
however, dosage should not exceed 2ml everyday. Make 5 partings of the hair
and put 5 drops in each part for best application.
Clinical side effects of Minoxidil treatment in female hair loss
Topical application on normal intact skin with Minoxidil is not well absorbed;
only 0.3 to 43.5 percent reaches the systematic circulation, which is eliminated
out of the system within 4 days from application. However, the effects on
absorption of concomitant occlusion and the systematic metabolic biotransformation
of topically applied Minoxidil are mostly unknown.
Contact dermatitis (scalp irritation, dryness, itching, scaling, and redness)
is the most common side effects of Minoxidil. Hypertrichosis – excessive
growth of hair in areas normally not hairy, a side effect of Minoxidil uncommon
to men, was known to affect 3 to 5% of women using Minoxidil. It’s
unclear why hypertrichosis occurs, but it is possibly through either a systemic
effect or via transfer of the drug. Areas commonly affected are the forehead,
malar areas, and sides of the face. This condition, however, may diminish
with continued treatment over the course of a year, or it resolves completely
within a few months once treatment is stopped. Predisposing factors of hypertrichosis
are existing facial hairs, higher dosage, and old age over 50 years. Care
should be taken to avoid manual spread of the agent by pillows to sites
other than the scalp, but local absorption is still believed to be the cause
of the problem.
Change in blood pressure or any other systematic effects of Minoxidil solution
was not evident from studies done, but patients with cardiovascular disease
are advised to use the agent with caution. Pregnant and lactating mothers
are also advised to avoid using the product. Although there is no evidence
of teratogenicity in rats and rabbits, but the Minoxidil has been found
to be secreted through breast milk.