All About Propecia

Long-term treatment with finasteride 1 mg decreases the likelihood of developing further visible hair loss in men with androgenetic alopecia (male pattern hair loss).

There are no reports on the effects of pharmacologic treatment on the likelihood of developing further visible hair loss in men with androgenetic alopecia (AGA). Our objectives were to examine whether finasteride 1 mg treatment decreases the likelihood of developing further visible hair loss in men with AGA. We conducted an analysis of global photographic assessment data from two Phase III trials in which 1553 men with AGA received finasteride 1 mg/day or placebo for up to 5 years. Finasteride 1 mg treatment led to a 93% decrease relative to placebo in the 5-year likelihood of developing further visible hair loss (95% CI: 89-97%; p < 0.001). We conclude that, in men with AGA, treatment with finasteride 1 mg/day over 5 years led to a marked and sustained decrease in the likelihood of developing further visible hair loss.

Androgenetic alopecia (AGA) is a dihydrotestosterone (DHT)-mediated process, characterized by continuous miniaturization of androgen reactive hair follicles and accompanied by perifollicular fibrosis of follicular units in histological examination. Testosterone (T: 10(-9)-10(-7) M) treatment increased the expression of type I procollagen at mRNA and protein level. Pretreatment of finasteride (10(-8) M) inhibited the T-induced type I procollagen expression at mRNA (40.2%) and protein levels (24.9%). T treatment increased the expression of transforming growth factor-beta 1 (TGF-beta1) at protein levels by 81.9% in the human scalp dermal fibroblasts (DFs). Pretreatment of finasteride decreased the expression of TGF-beta1 protein induced by an average of T (30.4%). The type I procollagen expression after pretreatment of neutralizing TGF-beta1 antibody (10 mug/ml) was inhibited by an average of 54.3%. Our findings suggest that T-induced TGF-beta1 and type I procollagen expression may contribute to the development of perifollicular fibrosis in the AGA, and the inhibitory effects on T-induced procollagen and TGF-beta1 expression may explain another possible mechanism how finasteride works in AGA.

BACKGROUND: Finasteride, an inhibitor of type 2 5alpha-reductase, inhibits conversion of testosterone to dihydrotestosterone, resulting in a decrease in serum and scalp dihydrotestosterone levels believed to be pathogenic in androgenetic alopecia. Oral finasteride has been shown to be effective in the treatment of hair loss in men, while its efficacy in women has remained controversial.

METHODS: 5 postmenopausal women without clinical or laboratory signs of hyperandrogenism were given 2.5 or 5 mg/day oral finasteride for the treatment of pattern hair loss. Efficacy was evaluated by patient and investigator assessments, and review of photographs taken at baseline and at months 6, 12 and 18 by an expert panel.

RESULTS: Finasteride treatment improved scalp hair by all evaluation techniques. The patients’ self-assessment demonstrated that finasteride treatment decreased hair loss, increased hair growth and improved appearance of hair. These improvements were confirmed by investigator assessment and assessments of photographs. No adverse effects were noted.

CONCLUSIONS: Oral finasteride in a dosage of 2.5 mg/day or more may be effective for the treatment of pattern hair loss in postmenopausal women in the absence of clinical or laboratory signs of hyperandrogenism.