What starting dose, titration schedule, and monitoring are recommended for oral minoxidil in an adult male with androgenetic alopecia who has no uncontrolled hypertension, heart failure, severe cardiac disease, or known hypersensitivity?

Oral Minoxidil for Male Androgenetic Alopecia

Starting Dose

For adult males with androgenetic alopecia, start oral minoxidil at 2.5 mg once daily, with the option to increase to 5 mg daily after 3 months if response is inadequate and no significant adverse effects occur. 1, 2

• The typical starting dose range for male AGA is 1-5 mg/day, but 2.5 mg represents a balanced approach between efficacy and tolerability 1
• Studies demonstrate that 5 mg once daily produces significant hair growth (mean increase of 35.1 hairs/cm² at 24 weeks) with 100% of patients showing improvement 2
• Lower doses (0.5-1 mg) are reserved for women due to higher adverse effect rates 3, 4

Titration Schedule

Assess response and tolerability at 3 months; if inadequate response and good tolerance, increase to 5 mg once daily. 1, 2

• Efficacy is dose-dependent, with higher doses showing greater hair growth but increased side effects 1, 5
• Peak efficacy assessment should occur at 6 months, with photographic documentation at 3,6, and 12 months 3
• Maximum dose is generally 5 mg/day for hair loss indications 1, 5
• Doses above 5 mg significantly increase adverse effects (hypertrichosis 17.5%, tachycardia 3.5%) without proportional benefit for hair loss 3

Pre-Treatment Screening

Obtain baseline blood pressure, heart rate, and screen for cardiovascular disease before initiating treatment. 3, 4

• Mandatory cardiovascular screening is required before starting oral minoxidil 3
• Measure baseline BP and HR to establish reference values 4
• Oral minoxidil is contraindicated in patients with pericardial effusion or significant cardiovascular disease 3, 4
• While minoxidil at antihypertensive doses (5-100 mg) requires loop diuretics and beta-blockers, these are NOT required at low doses (≤5 mg) used for hair loss 6, 4

Monitoring Protocol

Reassess at 3 months with BP/HR measurement, then periodic BP checks if dose exceeds 2.5 mg daily. 4

• Monitor for orthostatic symptoms, edema, and tachycardia at each visit 3
• Despite minoxidil's 4-hour half-life, hypotensive effects may last approximately 72 hours 3, 1
• Evaluate efficacy at 3,6, and 12 months using standardized photographs 3
• No routine laboratory monitoring is required for low-dose use in healthy patients 2

Common Adverse Effects

Hypertrichosis (unwanted body/facial hair growth) is the most common side effect, occurring in 24-93% of patients depending on dose. 7, 5, 2

• Hypertrichosis is dose-dependent: 15-17% at ≤2.5 mg daily, increasing to 93% at 5 mg daily 8, 4, 2
• Lower limb edema occurs in 2-10% of patients and is associated with higher doses 7, 5, 2
• Cardiovascular symptoms (dizziness, tachycardia, hypotension) occur in only 1-3.5% at low doses 3, 5
• Pericardial effusion is a rare but serious idiosyncratic (Type B) adverse effect requiring vigilance 6, 3, 1

Key Clinical Pitfalls

• Do not confuse antihypertensive dosing guidelines (5-100 mg daily requiring diuretics/beta-blockers) with hair loss dosing (≤5 mg daily). The cardiovascular precautions in hypertension guidelines do not apply to low-dose use 6, 4
• Males tolerate higher doses better than females, who have higher overall adverse effect rates and require lower starting doses (0.5-1 mg) 3
• Efficacy appears greatest in the vertex area compared to frontal/temporal regions in male AGA 2
• Response rates range from 70-100% in androgenetic alopecia, making it highly effective when tolerated 5, 2