What is the recommended dosage of propranolol (beta blocker) for a patient with migraines?

Propranolol Dosing for Migraine Prevention

Start propranolol at 80 mg daily and titrate to a target range of 80-240 mg daily, with most patients achieving adequate control at 160 mg daily. 1

Starting Dose and Titration

• Begin with 80 mg once daily (using extended-release formulation) and increase gradually to minimize side effects 1, 2
• The FDA-approved dosing for migraine prophylaxis is 80 mg once daily initially, with gradual increases at 3-7 day intervals until optimal response is achieved 2
• The usual effective dose range is 160-240 mg once daily, with 160 mg being the most common therapeutic dose 1, 2
• Maximum dose can reach 320 mg daily, though doses exceeding this have not been established as safe or effective 2

Evidence Supporting Lower Doses

While guidelines recommend 80-240 mg daily, research demonstrates that approximately 73% of patients respond to low doses (around 1 mg/kg body weight, typically 40-80 mg daily), suggesting you can start conservatively and increase only if needed 3. A study using just 40 mg daily showed efficacy when combined with other agents 4. However, prioritize the guideline-recommended starting dose of 80 mg daily as this represents the consensus expert opinion 1.

Duration of Adequate Trial

• Allow 2-3 months at therapeutic dose before declaring treatment failure, as clinical benefits may not become apparent immediately 1
• The FDA label specifies that if satisfactory response is not obtained within 4-6 weeks after reaching maximal dose, discontinue therapy 2
• One long-term study showed success rates progressively increased throughout an entire year of treatment, suggesting patience with the medication is warranted 5

Indications for Starting Prophylaxis

Initiate propranolol when patients meet any of these criteria:

• ≥2 migraine attacks per month producing disability lasting ≥3 days per month 1
• Use of acute rescue medications >2 times per week 1
• Failure of or contraindications to acute migraine treatments 1

Critical Contraindications

Avoid propranolol in patients with:

• Bradycardia 1
• Second or third-degree heart block 1
• Hypersensitivity to propranolol 1

Common pitfall: Do not use beta-blockers with intrinsic sympathomimetic activity (like pindolol), as these are ineffective for migraine prevention 1.

Monitoring and Side Effects

• Common adverse effects include fatigue, depression, nausea, dizziness, and insomnia 1
• Monitor specifically for mood changes and sleep disturbances 1
• No routine monitoring of heart rate or blood pressure is required between appointments if the patient is well 1

When to Choose Propranolol Over Alternatives

• Propranolol is superior for pure migraine, while amitriptyline (30-150 mg daily) is more effective for mixed migraine and tension-type headache 1, 6
• Propranolol and timolol are the only beta-blockers with the strongest evidence for migraine prevention 1
• Propranolol is substantially less costly than CGRP antagonists while having similar efficacy 1
• Beta-blockers demonstrate better tolerability than topiramate, with 157 fewer discontinuations due to adverse events per 1000 treated people 1

Discontinuation Strategy

• When stopping treatment, reduce dosage gradually over several weeks to avoid rebound phenomena 1, 2
• This is particularly important in patients on higher doses or those who have been on therapy for extended periods 2