What is the recommended treatment and dosage of Finasteride (finasteride) for male pattern baldness?

Finasteride for Male Pattern Baldness

For male pattern hair loss, prescribe finasteride 1 mg once daily, which is the FDA-approved dose that demonstrates superior efficacy to lower doses while maintaining an acceptable safety profile. 1, 2

Recommended Dosage

• Finasteride 1 mg daily is the optimal and only recommended dose for male pattern hair loss in men aged 18-60 years 1, 2
• The 1 mg dose was established through dose-ranging studies comparing 5 mg, 1 mg, 0.2 mg, and 0.01 mg, where 1 mg demonstrated efficacy similar to 5 mg but superior to lower doses 3
• Do not use the 5 mg dose (indicated for benign prostatic hyperplasia) for hair loss, as the 1 mg dose provides equivalent DHT suppression and efficacy for this indication 2

Expected Timeline and Efficacy

• Counsel patients that visible improvement typically begins by 12 weeks, with maximal benefit at 1-2 years 1
• At 48 weeks, 58% of men show improvement on global photographic assessment compared to 6% with placebo 4
• After 2 years, 66% demonstrate improvement in vertex hair growth versus 7% with placebo, and 83% have no further hair loss compared to baseline 5
• Efficacy is maintained over 5+ years, but hair loss resumes if treatment is discontinued, so plan for long-term therapy 1, 2
• In patients over age 30, better long-term improvements are observed, while 42.8% of men aged 20-30 may not improve even after 10 years 6

Critical Safety Considerations

PSA Monitoring

• Finasteride 1 mg reduces PSA levels by approximately 50% after 12 months of therapy 1, 2
• In men approaching prostate cancer screening age (>40-45 years), obtain a baseline PSA before starting treatment 1
• When screening for prostate cancer, PSA values must be doubled after 12 months of finasteride therapy to accurately interpret results 2

Sexual Side Effects

• Approximately 2-4% more patients experience sexual dysfunction compared to placebo, including decreased libido, ejaculation disorders, and erectile dysfunction 1
• The overall incidence of sexual function disorders is 3.8% with finasteride versus 2.1% with placebo 5
• All sexual adverse events are reversible upon discontinuation, and many resolve even with continued therapy 5
• While the 1 mg dose has inconclusive evidence regarding direct fertility impact, sexual side effects may indirectly affect fertility by impacting sexual function 1

Common Pitfalls to Avoid

• Do not prescribe finasteride for hair loss without counseling on realistic expectations regarding the 12-week onset and 1-2 year timeline for maximal benefit 1
• Do not fail to discuss the need for long-term treatment, as discontinuation results in resumption of hair loss 1, 2
• Do not overlook PSA considerations in men over 40-45 years who may need prostate cancer screening 1
• Finasteride is contraindicated in pregnant women due to risk of hypospadias in male fetuses 5

Combination Therapy Option

• When monotherapy provides insufficient results, combining finasteride 1 mg with minoxidil (topical or oral) may achieve superior results through complementary mechanisms—finasteride blocks DHT conversion while minoxidil promotes follicular growth through vasodilation 1
• No drug-drug interactions exist between these medications 1
• If using oral minoxidil, monitor for hypotension, tachycardia, fluid retention, and hypertrichosis 1