Side effects

Side effects of calcium channel blockers may include:

• Constipation
• Dizziness
• Fast heartbeat (palpitations)
• Fatigue
• Flushing
• Headache
• Nausea
• Rash
• Swelling in the feet and lower legs

Avoid grapefruit products while taking certain calcium channel blockers. Grapefruit juice interacts with the drug and can affect heart rate and blood pressure. This can cause symptoms such as headaches and dizziness.