From the FDA Drug Label
The initial oral dose is 80 mg propranolol hydrochloride extended-release capsules once daily. The usual effective dose range is 160 to 240 mg once daily.
The lowest dose of propranolol for migraine is 80 mg once daily 1.
From the Research
The lowest effective dose of beta blockers for migraine prevention should start at 20-40 mg twice daily for propranolol, with a minimum effective dose of 40 mg daily for most patients, as supported by the most recent and highest quality study 2. When considering beta blocker therapy for migraine prevention, it's essential to start at the lowest dose and gradually increase until achieving adequate migraine control or until side effects occur.
- Propranolol typically starts at 20-40 mg twice daily, with a minimum effective dose of 40 mg daily for most patients.
- Metoprolol can begin at 25-50 mg daily.
- Timolol may start at 5 mg twice daily, while atenolol often begins at 25 mg daily.
- Nadolol usually starts at 20-40 mg daily. These medications work by blocking beta-adrenergic receptors, which helps reduce vascular reactivity and stabilize serotonin systems involved in migraine pathophysiology, as explained in 3. Patients should take these medications consistently rather than as needed, as the preventive effect builds over 4-8 weeks. Common side effects include fatigue, dizziness, and reduced exercise tolerance, as noted in 4. Beta blockers should be used cautiously in patients with asthma, diabetes, or certain cardiac conditions. The most recent study 2 found that propranolol reduced episodic migraine headaches by 1.5 headaches/month at 8 weeks and was more likely to reduce headaches by 50%, making it a viable option for migraine prevention.