Examples
| Generic Name | Brand Name |
|---|
| amlodipine besylate | Norvasc |
| diltiazem hydrochloride | Cardizem, Tiazac |
| felodipine | Plendil |
| nifedipine | Adalat |
| verapamil hydrochloride | Isoptin SR |
How It Works
Calcium channel blockers help treat
coronary artery disease by:
- Increasing blood flow to the heart muscle by
expanding (dilating) the coronary arteries.
- Possibly help to
prevent a spasm of the coronary arteries.
- Lowering blood pressure
and the workload on the heart, which allows the heart muscle to function with
less oxygen and blood flow.
- Sometimes slowing a rapid heart rate
and controlling irregular heart rhythms.
Why It Is Used
Calcium channel blockers are commonly used in people with coronary
artery disease who have one or more of the following conditions:1
-
Stable angina
- Episodes of
spasm affecting the coronary arteries
- Inability to take
beta-blockers, or beta-blockers are ineffective in controlling a rapid heart
rhythm
How Well It Works
Calcium channel blockers can help reduce the severity and
frequency of chest pain when beta-blockers cannot be used.1 Unlike beta-blockers, however, these medications do not
reduce your risk of a future heart attack.
Side Effects
Side effects vary depending on the drug, but may include:
- Slowed heart rate or irregular heart
rhythm.
- Flushing, a pounding sensation in the head, dizziness,
headache.
- Leg swelling.
- Decreased blood
pressure.
- Tingling sensations in the arms or
legs.
- Weakness.
- Constipation.
Nifedipine, verapamil, and diltiazem may cause skin rash or breast
enlargement.
See Drug Reference for a full list of side effects. (Drug Reference
is not available in all systems.)
What To Think About
Calcium channel blockers are most effective when they are combined
with nitrates and beta-blockers, but their dosage must be monitored carefully
to prevent side effects. Nifedipine, amlodipine, and felodipine
are used most commonly in people already taking beta-blockers. You
can also take amlodipine in a combination dose with the
statin atorvastatin, which treats high cholesterol.
Therefore, this combination helps reduce chest pain and treats high cholesterol
at the same time.
In general, the long-acting forms (taken once a day) of calcium
channel blockers are preferred over the short-acting forms (taken 2 to 4 times
per day).
Verapamil, diltiazem, and nifedipine may worsen heart failure.
Amlodipine and felodipine do not appear to worsen heart
failure.
Verapamil or diltiazem sometimes are used when a person cannot take
beta-blockers.
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to help you understand this medication.