Calcium channel blockers for cluster headaches


Generic Name Brand Name
verapamil hydrochloride Calan, Verelan

How It Works

It is not clear exactly how verapamil hydrochloride works to prevent cluster headaches.

Why It Is Used

Verapamil hydrochloride is used to prevent cluster headaches.

How Well It Works

Verapamil hydrochloride is highly effective at preventing episodes of cluster headaches and chronic cluster headaches. About two-thirds of those taking daily doses improve by more than 50%.1 Verapamil hydrochloride is sometimes combined with other medicines, such as ergotamine or lithium, to effectively treat chronic cluster headaches.

Side Effects

Usually, verapamil causes very few side effects. Verapamil may cause:

  • Constipation.
  • Orthostatic hypotension (low blood pressure upon standing).
  • Water retention, such as swollen legs.
  • Fatigue.
  • Changes in or problems with the way your heart beats (heart rhythm abnormalities).

See Drug Reference for a full list of side effects. (Drug Reference is not available in all systems.)

What To Think About

People taking verapamil need to be watched closely and have regular tests when taking this medicine. Because verapamil can affect how the heart beats (its rhythm), this medicine should be used with caution in people who have problems with the electrical system that regulates the heart rate (a condition called heart block). Some research shows that all people taking this medicine should regularly have a test called an electrocardiogram (ECG or EKG) to make sure the heart's rhythm is still normal.2

Complete the new medication information form (PDF)(What is a PDF document?) to help you understand this medication.



  1. Ekbom K, Hardebo JE (2002). Cluster headache: Aetiology, diagnosis, and management. Drugs, 62(1): 61–69.
  2. Cohen AS, et al. (2007). Electrocardiographic abnormalities in patients with cluster headache on verapamil therapy. Neurology, 69(7): 668–675.

Last Updated: April 11, 2008

related physicians

related services

Bon Secours International| Sisters of Bon Secours USA| Bon Secours Health System

This information does not replace the advice of a doctor. Healthwise disclaims any warranty or liability for your use of this information. Your use of this information means that you agree to the Terms of Use. Privacy Policy. How this information was developed to help you make better health decisions.

© 1995-2010 Healthwise, Incorporated. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.