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Calcium channel blockers

Calcium channel blockers can help treat high blood pressure, abnormal heart rhythms and chest pain. Read about the types of calcium channel blockers, how they work and their possible side effects.

Types of calcium channel blockers

  • amlodipine, also called Apo-Amlodipine, Auro Amlodipine, Norvasc 
  • diltiazem, also called Apo-Diltiazem, Cardizem CD, Dilzem
  • felodipine, also called Felo ER, Plendil ER
  • nifedipine, also called Adalat, Adalat Oros, Nyefax Retard, Adefin XL
  • verapamil, also called Isoptin, Verpamil

How do they work?

Calcium channel blockers stop too much calcium from entering the heart cells. This helps lower blood pressure, reduce heart pain (angina), treat abnormal heart rhythms (such as atrial fibrillation) and reduce your risk of stroke.

Calcium channel blockers side effects

You may experience some unwanted side effects when taking calcium channel blockers.

These can include:

  • swelling of the ankles or feet
  • light-headedness and/or feeling dizzy
  • lower blood pressure and slower heart rate.

Ring 111 if you have any of the following:

  • severe chest pain
  • severe headache
  • acute shortness of breath
  • swelling of your mouth, lips or tongue, as this could be an allergic reaction.

Talk to your doctor if your side effects are worrying you. Don't stop taking your medication without talking to your doctor first. The benefits usually outweigh the side effects.

What checks do I need?

You are likely to have regular blood pressure and heart rate checks while taking calcium channel blockers. 

You're also likely to have regular blood tests to check your blood and kidney function.

What happens if I miss a dose?

It's important to take your medication daily and not to skip a dose.

If you forget to take a dose, take it immediately, then continue as normal the following day. However, if it's almost time for the next dose, skip the missed dose and continue as normal.

Do NOT take a double dose.

What else do I need to know?

Tell your health professionals if you're taking any: 

  • supplements
  • natural medicines
  • vitamins
  • alternative therapies. 

These can sometimes make your heart beta blockers less effective. 

If you are taking certain calcium channel blockers you should not eat grapefruit or drink grapefruit juice, as it can make your medication less effective. Talk to your doctor or pharmacist to see if this applies to your medication. 

Talk to your doctor if you:

  • have kidney, lung or liver conditions
  • are planning to get pregnant or are breastfeeding.

Related treatments and conditions


Atrial fibrillation


Blood pressure

Heart attack

Search for another heart medication