Androgenic Alopecia — DHT-Driven Follicle Miniaturization
Placeholder lead: DHT binds receptors, shrinking susceptible follicles over years.
- Dermal papilla: Type II 5-AR location (placeholder short caption)
- ~5x testosterone: DHT receptor affinity (placeholder short caption)
- ~50%: Affected men by 50 (placeholder short caption)
- Years: Miniaturization span (placeholder short caption)
How DHT shrinks follicles
Placeholder body text: DHT signaling shortens anagen phase, follicles shrink cycle by cycle.
Genetic susceptibility factors
Placeholder body text: androgen receptor gene variants set individual sensitivity levels.
Placeholder highlight: miniaturization is gradual and reversible early on.
Finasteride Inhibits 5α-Reductase Type II
Placeholder lead: finasteride binds the enzyme active site, blocking its function.
- 5-AR Type II: Target enzyme (placeholder short caption)
- 1 mg/day: Standard oral dose (placeholder short caption)
- Competitive: Inhibition mechanism (placeholder short caption)
- Weeks: Onset of action (placeholder short caption)
Enzyme active-site blockade
Placeholder body text: finasteride forms a stable complex occupying the catalytic pocket.
Dose adherence matters
Placeholder body text: consistent daily dosing sustains enzyme inhibition levels.
Placeholder highlight: missed doses let enzyme activity partially rebound.
Scalp DHT Levels Drop Roughly 70%
Placeholder lead: blocked conversion sharply lowers local scalp DHT concentration.
- ~70%: Scalp DHT reduction (placeholder short caption)
- ~70%: Serum DHT reduction (placeholder short caption)
- Slightly up: Testosterone level (placeholder short caption)
- ~1 month: Steady state reached (placeholder short caption)
Where the blocked testosterone goes
Placeholder body text: unconverted testosterone remains available, DHT pathway suppressed.
Follicular DHT exposure falls
Placeholder body text: lower local DHT reduces androgen receptor signaling at follicles.
Placeholder highlight: type I 5-AR still produces some residual DHT.
Miniaturization Halts, Regrowth Begins
Placeholder lead: surviving follicles re-enter longer anagen growth phases.
- ~Month 2–4: Shedding phase (placeholder short caption)
- ~Month 4–6: Visible thickening (placeholder short caption)
- Increases: Anagen phase length (placeholder short caption)
- Unchanged: Follicle count (placeholder short caption)
Recovery curve over months
Placeholder body text: thickening progresses gradually, plateauing near a year.
Temporary shed before regrowth
Placeholder body text: early synchronized shedding often precedes visible improvement.
Placeholder highlight: fully miniaturized follicles rarely fully recover.
Density Stabilizes — Reversible if Stopped
Placeholder lead: sustained therapy maintains gains; stopping resumes miniaturization.
- 6–12 mo: Plateau reached (placeholder short caption)
- Majority: Continued users improved (placeholder short caption)
- Reverses: Effect after stopping (placeholder short caption)
- ~12 months: Reversal timeframe (placeholder short caption)
Maintaining long-term gains
Placeholder body text: ongoing daily therapy is required to preserve density gains.
What happens if therapy stops
Placeholder body text: DHT rebounds and miniaturization resumes within months.
Placeholder highlight: benefit is maintenance, not a permanent cure.