Finasteride (Propecia) finasteride

Finasteride is FDA-approved for male pattern hair loss (androgenetic alopecia) and is one of the most-studied hair loss treatments. In trials, approximately 80-90% of men taking 1mg daily for one year either maintained their existing hair or experienced some regrowth. Regrowth tends to be more modest than slowing/stopping further loss; significant regrowth happens in roughly 30-40% of users. Effects typically appear after 3-6 months and continue for 12+ months. Discontinuation usually leads to gradual return to the natural hair loss trajectory over 6-12 months. Side effects are uncommon (~2-4% report sexual side effects in trials) but should be discussed with a clinician.

Finasteride and minoxidil work through different mechanisms and are often combined for best results. Finasteride is an oral 5-alpha-reductase inhibitor that lowers DHT — the hormone driving male pattern hair loss — addressing the root cause. Minoxidil (topical or oral) increases blood flow to hair follicles and prolongs the growth phase, addressing the downstream symptom. In studies, the combination produces meaningfully better outcomes than either drug alone: combination users see more regrowth and better maintenance over time. Side-effect profiles are different (finasteride has potential sexual side effects; minoxidil can cause shedding initially and unwanted facial hair if applied carelessly). Most telehealth services offer both as a combined protocol.

Visible effects of finasteride typically appear at 3-6 months of consistent daily use, with maximum benefit at 12-18 months. A common early experience is increased shedding around weeks 4-12 — paradoxically, this often signals the medication is working (shorter, weaker hairs are being pushed out as stronger hairs grow in). Stopping during the shed phase is the most common mistake; patients who continue typically see regrowth catch up to and surpass the shed. Documented outcomes at 12 months: ~80-90% of users maintain existing hair or experience some regrowth, with meaningful regrowth in 30-40%. Combining finasteride with minoxidil typically produces better results than either alone. Discontinuation results in gradual return to the natural hair-loss trajectory over 6-12 months. Effects are not permanent — continuous use is required for ongoing benefit.

Oral finasteride (1mg daily) has the longest track record, lowest cost (~$10-30/mo generic), and the most-studied efficacy data. The trade-off is potential systemic side effects, most notably sexual side effects (libido reduction, erectile dysfunction) reported by ~2-4% of trial users. Topical finasteride (typically 0.25% solution applied to scalp daily) delivers DHT-blocking effect at the scalp with substantially lower systemic absorption — clinical data suggests comparable scalp efficacy with reduced sexual side-effect risk. Costs more ($40-80/mo, compounded), not typically covered by insurance. Some patients tolerate topical when oral caused side effects; others want the convenience of a daily pill. Combining topical finasteride with topical minoxidil is a common protocol. For patients with no side effects on oral, switching to topical may not be worth the cost increase.

No direct interaction. Both can affect mood independently. If depression history, keep alcohol moderate while assessing finasteride effect on mood.

Most side effects resolve in weeks after stopping. A minority report persistent symptoms (PFS) — sexual, mood, cognitive. Medical community is divided. FDA label acknowledges reports. Consider topical finasteride if concerned.