What it is
Propecia contains the active ingredient finasteride, a 4-azasteroid 5-alpha-reductase inhibitor, taken as a 1 mg film-coated tablet, with or without food, once a day. Propecia holds national authorisations rather than a single EU-wide one; the details here come from the Spanish authorisation (AEMPS CIMA registration 62441, holder Organon Salud, S.L.), authorised since 1 February 1999. The authorised age band is narrow — men aged 18 to 41 with androgenetic alopecia — and it is not authorised for use in women.Active ingredient: finasteride. Dosage: 1 mg / day.
How it works
Male pattern hair loss is driven by dihydrotestosterone (DHT), a hormone the body makes from testosterone. A balding scalp contains miniaturised follicles and higher amounts of DHT, so each growth cycle produces a thinner, shorter hair until visible growth stops. Finasteride blocks the 5-alpha-reductase type II enzyme that converts testosterone into DHT, so less DHT reaches the scalp.1
Months 1–3
Daily 1 mg; changes build silently.
2
Months 3–6
Shedding stabilises.
3
Months 6–12
Visible improvement is assessed.
What the studies reported
The pivotal programme comprised two 1-year, multicentre, randomised, double-blind, placebo-controlled trials in 1,553 men aged 18–41 with androgenetic alopecia (vertex-pattern loss), followed by a blinded extension for a second year in 1,215 men (Kaufman et al., J Am Acad Dermatol 1998, PMID 9777765). The primary endpoint was scalp hair count in a 5.1 cm² circular area (1-inch diameter) of balding vertex scalp. Mean baseline hair count was 876. Finasteride 1 mg/day produced a net increase of 107 hairs at 1 year and 138 hairs at 2 years versus placebo (both p < 0.001), while the placebo group showed progressive loss. The trials did not enrol men with bitemporal recession or late-stage hair loss, so no conclusion can be drawn about those patterns. The EU product information states continued use is needed to keep the benefit. The authorised age band is men aged 18–41.What has been reported
About 1% of men in each group stopped treatment for a sexual side effect in the first 12 months (EU SmPC, section 4.8). Persistence of decreased libido, erectile dysfunction and ejaculation disorders after finasteride is stopped has been reported in post-marketing use, at a frequency that is not known because these are spontaneous reports. Male breast cancer has been reported during post-marketing use; frequency cannot be estimated from the available data.
Who it is not suitable for
The EU product information contraindicates use in women, because finasteride can cause abnormalities of the external genitalia in a male foetus if taken during pregnancy. The authorised age band is men aged 18 to 41.Female hair loss sometimes involves finasteride prescribed off-label, at a different dose and under different safeguards. See the finasteride for female hair loss guide.
How Hi-Doctor handles it
Our doctors review every hair-growth option and recommend what fits your history and goals. An EU-licensed doctor reviews your case and, if eligible, issues an electronic prescription valid at any EU pharmacy under Directive 2011/24/EU. See how it works for the full process, pricing for the consultation fee, and topical minoxidil for another EU-authorised hair-growth option.Start a consultation
Hair-growth consultation
Answer the hair-growth questionnaire and a registered doctor reviews it.
They decide whether treatment is appropriate, which one, and at what dose —
and declining is a normal outcome. See what it costs
and how the review works.