Side effects

Possible side effects of calcium channel blockers are:

• Constipation.
• Dizziness.
• Fast heartbeat you can feel.
• Extreme tiredness.
• Flushing.
• Headache.
• Nausea.
• Swelling in the feet and lower legs.

Do not eat grapefruit or grapefruit products while taking the calcium channel blockers diltiazem and verapamil. Grapefruit juice interacts with these medicines and can affect heart rate and blood pressure. This can cause symptoms such as headaches and dizziness.

Talk with your healthcare team if you have any questions about the medicines you take.