Finasteride, a synthetic 4-azasteroid compound, reduces the dihydrotestosterone
(DHT) production which in turn limits the action of DHT on scalp hair
follicles. It is used primarily by men older than 18 years old diagnosed
with male pattern hair loss.
Finasteride acts as a potent 5 -reductase inhibitor without the help
of any androgenic, antiandrogenic, or other steroid hormone activities.
Androstenedione conversion to 5a-androstanedione and the formation of
potent DHT from testosterone is prompted by the microsomal enzyme steroid
5 -reductase. It was found out that Finasteride has a higher affinity
for the 5 -Reductase – 2 (5 R-2) compared to 5 -Reductase – 1
Clinical trials in male pattern hair loss
There are documented effects of Finasteride that usually acts by reversing
the pathogenesis of hair loss in male pattern baldness. Majority
of these studies showed the effects of Finasteride in the stimulation
of a substantial amount of hair re-growth, reaching the highest effectivity
of the treatment after one year as it eventually slowed down the rate
of hair loss progression.
- The three clinical trials that involved placebo-controlled double
blinds conducted recently has shown that taking 1mg Finasteride daily
least 12 months prevents the progression of hair loss. It has also
been seen to produce greater increase in hair counts compared to the
noted with placebo on men with mild to moderate hair loss. 48% of
the subjects showed clinical improvement in the 1 year treatment compared
to the 7% of the subjects undergoing placebo treatment as the photographs
had indicated. The figures increased to 66% at the end of the second
- Macrophotographs measured increasing total hair counts, increased
anagen hair count, and increased anagen to telogen ratio in a study
Finasteride as a treatment. The same study showed that the probability
that Finasteride is the agent responsible for the stimulation of
conversion of hair follicles into the anagen phase, through reversion
decrease in the anagen phase and increase in the lag phase, is strong.
- The stimulation of an increase in terminal count and the decrease
in the vellus hair count was found to be caused by Finasteride in
of scalp biopsy.
- An objective measurement of hair count and
hair weight was used in one study to the demonstration that both hair
count and hair
exponentially (with a larger increase on hair weight) upon treating
pattern baldness with Finasteride. It asserts the ability
of the drug to reverse
miniaturization process, production of longer hair and volume,
and a possibility of high growth rate.
- The efficiency of Finasteride
as an alternative mode of administration has also been studied. When
0.05% Finasteride solution was applied
to the scalp, it had no direct effect on hair growth although
it was well
absorbed by the scalp and was able to produce 40% production
in serum DHT. This could be because a reduction in circulating
in addition to the local blockade of 5a-reductase at the hair
follicle for Finasteride to take effect.
- There are concurrent
evaluations of the effects of 1mg Finasteride in older men with extensive
hair loss as well as those with
Efficacy in Men
1mg a day of Finasteride was approved for treating male patients with
pattern baldness in the US and in several European countries. Doses
of oral Finasteride at 1mg and 5mg a day were able to suppress serum DHT
at 71.4% and 72.2% respectively. It was also found out that scalp DHT
suppression at 64.15 and 69.4% resulted from the same doses. The period
of visibility for the treatment to occur is at least six months although
its effects is more apparent on vertex balding than in frontal hair loss
(although the medication increases re-growth in the frontal area as well.
Finasteride is available in the market as Propecia and had been proven
to maintain or increase hair count in men. This drug was developed to
treat pattern baldness in the vertex and anterior mid-scalp area.
Combined use of Finasteride and topical Minoxidil
Studies on small-scale variably-controlled experiments using combination
of Finasteride and Minoxidil that showed effectivity when the two are
combined compared to any drug alone were conducted on a primate model
with pattern baldness as well as on young men with mild to moderate
male pattern hair loss. Although the success of this study had been verified,
there is still a need for further investigation to sustain the theory.
Side effects in Men
Decreased libido, decreased semen volume, and erectile dysfunction are
some of the common side effects experienced by men on Finasteride treatment.
All of these occur in less than 2% of men younger than 41 and relatively
more often occurring in older men. However, a study conducted by Overstreet
et al showed that Finasteride 1mg daily for 48 weeks does not affect spermatogenesis
(semen production) in men aged 19 to 41 years.
Finasteride for men had been in medical use for over 10 years, suggesting
its safety in use. A considerable number of elderly men using this drug
were using 5mg a day and no evidences were found having negative effects
of long term use on bone mineral density. Reversible painful gynaecomastia
(abnormal enlargement of the male mammary glands) had been reported and
the significant percentage of the incidence is at 0.001%. The adverse
effects in men using Finasteride were resolved while they are still under
medication and all other remaining adverse effects vanished when the intake