Male pattern hair loss affects roughly half of men by age fifty and the majority by seventy. It's genetic, hormonal, and progressive. It's also — for the first time in medical history — genuinely treatable, provided you start early and set realistic expectations.
The treatments that work do so by interrupting a specific hormonal pathway or improving follicular health. The treatments that don't work fail predictably because they don't address that pathway. Sorting the two isn't hard once you understand the mechanism.
The mechanism
Androgenetic alopecia is driven by dihydrotestosterone (DHT), a metabolite of testosterone produced by the enzyme 5-alpha-reductase. In genetically susceptible follicles — mostly on the top and front of the scalp — DHT progressively shrinks the follicle through successive growth cycles. Hairs get thinner, shorter, and lighter until the follicle stops producing visible hair entirely.
The pattern is stereotyped: temporal recession, then vertex thinning, then eventual convergence. The back and sides of the scalp are largely DHT-resistant, which is why hair transplants work — those follicles retain their resistance when moved.
Genetics dominate. If your father, maternal grandfather, and uncles are bald, you're likely to be too. But timing and severity vary enough that intervention matters.
What actually works
Three interventions have strong evidence. Everything else is either adjunctive or marketing.
Finasteride (oral) blocks 5-alpha-reductase and reduces scalp DHT by roughly 60 percent. It halts progression in most men and produces cosmetic regrowth in a meaningful minority. It works only while you take it; stopping returns you to your genetic trajectory within a year. Side effects — sexual dysfunction, mood changes — are uncommon but real and warrant an honest conversation with a prescriber. Topical finasteride is emerging as an option with lower systemic exposure.
Minoxidil (topical or oral) extends the anagen (growth) phase of the follicle. Mechanism is incompletely understood but effect is consistent. Topical 5% is over-the-counter; low-dose oral minoxidil (typically 1.25–5 mg) has become common off-label use and is often more effective and easier to comply with. Initial shedding in the first few months is expected, not a treatment failure.
Hair transplantation (follicular unit extraction or strip harvesting) moves DHT-resistant follicles to thinning areas. It's the only truly permanent option. Results depend heavily on surgeon skill and on whether medical therapy continues to protect native hair — transplanting without treating the underlying process leaves you with islands of transplanted hair surrounded by ongoing recession.
Adjuncts with modest evidence
- Ketoconazole shampoo (2%) has anti-androgenic activity at the scalp and some evidence of modest benefit
- Low-level laser therapy devices show small effects in controlled trials
- Platelet-rich plasma (PRP) injections have mixed evidence; likely modest benefit at real cost
- Microneedling may improve minoxidil absorption and stimulate follicles
These are worth considering after the big three are on board, not instead of them.
What doesn't work
Biotin supplements do nothing unless you're deficient, which is rare. Saw palmetto has weaker evidence than finasteride and inconsistent dosing. Scalp massage, castor oil, onion juice, and most social-media protocols have no meaningful effect. Hats do not cause baldness.
The single biggest predictor of treatment success is how early you start. Follicles you've already lost can't be revived by medication.
Timing and expectations
Start when you first notice thinning, not when you've lost half your hair. Medical therapy protects follicles that are miniaturizing; it can't resurrect dead ones. A dermatologist can confirm the diagnosis (ruling out telogen effluvium, alopecia areata, and nutritional causes) and set a treatment plan.
Expect maintenance more than regrowth. If your hair looks the same in five years, the treatment is working. Photographs from the same angle every six months are more honest than mirror impressions.
The bottom line
Male pattern baldness is progressive but no longer inevitable in its full expression. Finasteride, minoxidil, and — when indicated — transplantation are the interventions with real evidence. Start early, be consistent, and ignore the supplement industry.