What is finasteride? Finasteride (brand: Propecia at 1 mg; Proscar at 5 mg) is a 5-alpha reductase inhibitor that lowers scalp DHT. It's FDA-approved for male pattern hair loss at 1 mg daily.
Finasteride 1 mg is an FDA-approved oral treatment for male pattern hair loss. It can slow further loss and help some men regrow hair. A clinician reviews the pattern, medical history and possible side effects before prescribing.
Finasteride inhibits the enzyme 5-alpha reductase, which converts testosterone into dihydrotestosterone (DHT). DHT is the hormone driving miniaturization of hair follicles in genetically susceptible men. Lower DHT means follicles stay in the growth phase longer, shed less, and — over 6 to 12 months — often produce thicker, longer hairs.
Preserving existing hair is a meaningful result even without dramatic regrowth. Benefit generally takes at least three months; your clinician can compare progress over six to twelve months. Effectiveness at bitemporal recession is not established in the label.
The labeled hair-loss dose is 1 mg once daily, with or without food. If you forget a tablet, take the next one as usual; do not take an extra dose. More than once daily does not improve results. Continued use is needed to maintain benefit.
In first-year trials, 3.8% of men taking finasteride and 2.1% taking placebo reported one or more of decreased libido, erectile dysfunction or ejaculation disorder. Breast changes and allergic reactions have also been reported. The label separates trial findings from postmarketing reports, whose frequency cannot be reliably estimated.
Sexual symptoms continuing after stopping, depression and suicidal thoughts or behavior appear in postmarketing labeling. Report sexual changes promptly. Stop finasteride 1 mg and seek medical advice for mood changes; get immediate emergency help for thoughts you may act on. Trouble breathing or swelling of the lips, tongue or throat needs emergency care. Read the fuller side-effect guide.
$45 online visit — no required subscription, no automatic subscription renewal. Medication cost is paid separately at the pharmacy and varies by medication, quantity, pharmacy, insurance, and discount-card pricing.
These sources support the medication facts and research discussed above. Study results apply to the doses and populations tested; they do not guarantee an individual outcome.
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