Verapamil Dosing for Cluster Headache
Start verapamil at 240 mg daily (divided doses) and titrate upward based on attack control, with most patients requiring 360-720 mg daily for effective prophylaxis, though recent guidelines note insufficient evidence for formal recommendation. 1, 2
Initial Dosing Strategy
- Begin with 240 mg daily as the minimum effective dose, typically divided into three doses (e.g., 40 mg morning, 80 mg afternoon, 80 mg evening) 2, 3
- The 360 mg daily dose is the only dosage proven superior to placebo in controlled trials 4, 2
- However, clinical practice commonly requires 480-720 mg daily for adequate attack suppression 4, 2
Dose Titration Protocol
- Increase by 40 mg every 2 days, timing the increases based on when attacks occur 5:
- For nocturnal attacks: increase evening dose first, then afternoon dose
- For morning attacks: consider setting alarm 2 hours before usual wake time to take medication 5
- Continue titration until complete attack suppression is achieved 5
- Some patients may require 520-960 mg daily for full control 5
Efficacy by Cluster Headache Type
- Episodic cluster headache: 94% achieve complete relief with adequate verapamil dosing 5
- Chronic cluster headache: Only 55% achieve complete relief (69% men, 20% women), often requiring additional prophylactic agents 5
- Recent VA/DoD guidelines state there is insufficient evidence to recommend for or against verapamil for either episodic or chronic cluster headache 1, 6
Cardiac Monitoring Requirements
- Obtain baseline ECG before initiating therapy 4, 7
- Monitor PR interval with ECG when using doses >360 mg daily, as doses used in cluster headache may be double those used in cardiology 4, 7
- Cardiac adverse events reported with high-dose verapamil include complete AV block, sick sinus syndrome, sinus bradycardia, and syncope at doses ranging from 240-1200 mg daily 7
- Strict cardiac monitoring is required for off-label high-dose use 7
Important Caveats
- Verapamil is no longer the clear first-line choice: The 2023 VA/DoD guidelines recommend galcanezumab as first-line prophylaxis for episodic cluster headache with the strongest evidence 1, 6
- Verapamil should not be given to patients with impaired ventricular function, heart failure, or wide-complex tachycardias 8
- Continue the effective dose for 2 weeks after cluster period ends before systematic reduction 5
- For incomplete relief, add lithium, sumatriptan, or sodium valproate rather than abandoning verapamil 5