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What should I know about calcium channel blockers?

        Health | Headache

Calcium channel blockers are also called calcium antagonists. They were originally used to treat cardiovascular illnesses. That includes illnesses such as high blood pressure or hypertension, chest pain or angina, and ruptured blood vessels in the brain known as subarachnoid hemorrhage. They have also been used to prevent migraine headaches and cluster headaches. They will not help you once a headache has started.

Calcium channel blockers are most useful for people who have any of the following conditions:

  • migraine with prolonged aura
  • migraines that cannot be prevented by beta-blockers
  • other problems, such as asthma or slow or irregular heartbeat, that do not allow them to take beta-blockers

How do I take calcium channel blockers safely?

Follow these tips to get the most effective use from this medication.

  • Some conditions may worsen if you stop taking any of these medications suddenly. So keep taking your medication as prescribed. Do not stop taking it without first checking with your doctor. He or she may want you to reduce your dose gradually before stopping.
  • Remember to fill your prescriptions and refills on time to avoid missed doses.
  • Make sure that you have enough to last you on weekends, holidays, or when you travel.

How do calcium channel blockers work?

Calcium is a mineral involved in muscle contractions and electrical impulses in brain cells. Calcium channel blockers slow the movement of calcium into the cells of the heart and blood vessels. As a result, they relax blood vessels and increase the supply of blood and oxygen to various parts of the body. Because of these actions, they are very effective in treating many conditions.

How they work to prevent migraines is unclear. You must take them on a regular basis at the same time each day to effectively prevent headaches.

What are the possible side effects from using calcium channel blockers and what should I do about them?

All medications can cause side effects. You need to understand what these are and be prepared to handle them. Check with your doctor right away if you have any of these side effects while you're taking a calcium channel blocker:

  • chest pain or discomfort
  • difficulty breathing
  • slow or irregular heartbeats (fewer than 50 beats per minute)
  • swelling of your ankles, feet, or lower legs
  • wheezing or coughing

You should also check with your doctor if you experience any of these symptoms:

  • loss of balance
  • mental depression
  • a shuffling walk
  • trembling of your extremities

Other side effects may occur while you're taking calcium channel blockers. These side effects may include the following:

  • constipation
  • diarrhea
  • drowsiness
  • dry mouth
  • flushing and feeling warmth
  • headache
  • increased appetite or weight gain
  • lightheadedness
  • nausea
  • unusual tiredness or weakness

Some of these side effects may go away with time as you continue to take your medication. If they don't, you should mention them to your doctor.

What are the possible drug interactions with calcium channel blockers?

Talk with your doctor and pharmacist about possible drug interactions with calcium channel blockers. You should tell your doctor and pharmacist about all the other medications you are taking. You should also tell them about your other medical conditions, both past and present. This would include problems with heart rhythm, kidney or liver disease, depression, Parkinson's disease, or other heart and blood vessel problems. You need to keep your regular appointments while you take this medication so that your doctor can keep track of your progress.