80 million Americans have hair loss. July 2026 NIH PMC NMA ranked topical minoxidil 5% #1 across 23 studies. This complete guide covers finasteride (90% see results at 5 years), the post-finasteride syndrome warning every patient must hear, the oral minoxidil off-label boom, spironolactone for women, an 8-treatment comparison table, and why months 1–3 show nothing even when the drug is working.