What is the proper protocol for taking minoxidil (vasodilator) tablets for a patient with alopecia?

How to Take Minoxidil Tablet for Alopecia

Oral minoxidil should be started at 1 mg daily for women and 2.5 mg daily for men, but only after mandatory cardiovascular screening and only if topical minoxidil 5% has failed or cannot be tolerated, as topical therapy remains the first-line treatment. 1, 2

Critical Pre-Treatment Requirements

Before prescribing oral minoxidil, you must:

• Screen all patients for cardiovascular disease including baseline blood pressure, heart rate, rhythm assessment, and cardiovascular history 1, 2
• Avoid oral minoxidil entirely in patients with existing cardiovascular conditions due to rare but serious adverse effects including pericardial effusion 1, 2
• Confirm the patient has failed or cannot tolerate topical minoxidil 5% therapy, as topical remains first-line 1

Dosing Protocol by Sex

For Women:

• Start at 1 mg daily (lower starting dose required due to significantly higher incidence of adverse effects compared to men) 2, 3
• Maximum dose typically 1.25 mg daily 3

For Men:

• Start at 2.5 mg daily 3
• Can increase to 5 mg daily if needed 3
• Doses >5 mg are associated with increased adverse effects including hypertrichosis (17.5%) and tachycardia (3.5%) 2

Important Caveats About Efficacy

The type of alopecia matters critically:

• For androgenetic alopecia (pattern hair loss): Oral minoxidil 1 mg is as effective as topical 5% with response rates of 18-82.4% 2, 4
• For alopecia areata: While oral minoxidil shows 82% response rates in some studies 5, topical minoxidil has disappointing efficacy (only 32-33% response) and is not convincingly effective per British Association of Dermatologists guidelines 6, 7

Monitoring Requirements

At each follow-up visit, assess:

• Orthostatic vital signs (hypotensive effect may last 72 hours despite 4-hour half-life) 2
• Edema, particularly lower extremities 2
• Heart rate and rhythm 1
• Cardiovascular symptoms including dizziness and lightheadedness 2

Evaluate treatment response at 3,6, and 12 months using standardized photographs, trichoscopy, patient self-assessment questionnaires, and hair pull tests 1, 2

Common Adverse Effects to Counsel Patients About

• Hypertrichosis (unwanted hair growth): 17.5% incidence, most common side effect 2
• Lower extremity edema: 14.9% overall incidence at low doses 2
• Dizziness and lightheadedness: More common at doses >5 mg 2
• Tachycardia: 3.5% incidence 2

Absolute Contraindications

• Pre-existing cardiovascular disease 1, 2
• Pregnancy or planning pregnancy (lack of safety data) 2

Consider Combination Therapy Instead

Before escalating to oral minoxidil, consider combining topical minoxidil 5% with platelet-rich plasma (PRP), which shows superior efficacy to either treatment alone 1, 2. The protocol is: topical minoxidil 5% twice daily + PRP injections monthly for at least 3 sessions, then maintenance every 6 months 1, 2.

Duration of Treatment

Treatment must be indefinite - discontinuation leads to complete reversal of hair growth benefits, whether using topical or oral formulations 1