Propecia contains a medicine called finasteride. This belongs to a group of medicines
called Type II ‘5-alpha reductase inhibitors’.
Propecia is used for the treatment of male pattern hair loss (also known as androgenetic
alopecia). Propecia increases hair growth on the scalp and prevents further hair loss in
men. Men with mild to moderate, but not complete hair loss, can benefit from using
How does the hair on your head grow?
On average your hair grows about 1 centimetre (half an inch) each month. Hair grows
from hair follicles, which are located under your skin.
A single scalp hair grows continuously for 2-4 years (growth phase) and then stops
growing for 2-4 months (rest phase). After this the hair falls out. In its place a new
healthy hair begins to grow, and the cycle is repeated. The hairs on your scalp are
always in different stages of this cycle so it is normal to lose scalp hair every day.
What is male pattern hair loss?
Male pattern hair loss is a common condition in which men experience thinning of the
hair on the scalp, often resulting in a receding hairline and/or balding on the top of the
head. This condition is thought to be caused by a combination of genetic factors and a
particular hormone, DHT (dihydrotestosterone).
DHT causes a decrease in the growth phase and thinning of the hair (see picture). This
leads to male pattern hair loss. These changes can start to occur in some men in their
20s and become more common with age. Once hair loss has occurred over a long
period of time, the hair may be permanently lost.