oralPropeciaProscar (higher dose)generic finasteride

Finasteride — Side Effects, Dosage & Consistency Guide

Finasteride 1mg (brand name Propecia) is the gold-standard oral DHT blocker for male androgenic alopecia. It works by inhibiting 5-alpha-reductase type II, reducing serum DHT by approximately 70%. Consistency is critical — missing doses can cause a hormone rebound that accelerates shedding.

How it works

DHT (dihydrotestosterone) binds to androgen receptors in genetically susceptible hair follicles, causing the follicle to miniaturize over time. Finasteride blocks the enzyme (5α-reductase type II) that converts testosterone to DHT, reducing scalp DHT levels by 60–70% and halting follicle miniaturization.

Side effects

Decreased libido

Uncommon

Erectile dysfunction

Uncommon

Reduced ejaculate volume

Uncommon

Breast tenderness (gynecomastia)

Uncommon

Depression or mood changes

Uncommon

Post-Finasteride Syndrome (persistent sides after stopping)

Rare

Testicular pain

Rare

Safety considerations

  • Pregnant women must not handle crushed or broken tablets — finasteride causes birth defects.

  • Side effects are reversible on discontinuation for most users.

  • A catch-up shed can occur if doses are missed for 1+ weeks.

  • PSA (prostate-specific antigen) levels will be approximately halved — inform your doctor.

  • Monitor mood changes; stop and consult if persistent depression occurs.

Quick Reference

Typical Dose

1mg once daily, taken with or without food

Onset Time

6–12 months to see reduced shedding; full density recovery at 18–24 months

Category

oral

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Medical disclaimer: The information on this page is for educational purposes only and does not constitute medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider or dermatologist before starting, stopping, or modifying any medication or treatment protocol. Hair loss medication interactions and individual responses vary significantly.