9 Essential Tips for Taking Calcium Channel Blockers
Key takeaways:
Calcium channel blockers (CCBs) are prescription-only medications that treat high blood pressure and other heart conditions. Diltiazem (Cardizem) and amlodipine (Norvasc, Katerzia) are a couple of examples.
Meals and snacks don’t affect how most CCBs work. But some of them — such as felodipine ER, nimodipine (Nymalize), and nisoldipine (Sular) — work best on an empty stomach.
There are ways to save on CCBs. Many options are available as lower-cost generics or have copay savings programs. A GoodRx coupon may also be able to make your prescription more affordable.
Access savings on related medications
Table of contents
Calcium channel blockers (CCBs) are popular, go-to medications that treat a variety of heart-related health conditions. Hypertension (high blood pressure) and coronary artery disease are a couple of examples. In fact, CCBs are first-choice medications for managing hypertension.
If your healthcare provider recommends that you take a CCB, it’s natural to have questions. After all, it can be tough to interpret information about side effects, missed doses, and meal timing. The nine pharmacist-backed tips below can help you get the most out of your CCB.
1. Calcium channel blockers are prescription-only medications
You won’t be able to find any CCBs over the counter (OTC). They’re only available with a prescription from your healthcare provider.
There are two main groups of CCBs: non-dihydropyridine (non-DHP) and dihydropyridine (DHP). Non-DHP CCBs focus on controlling your heart rate. Diltiazem (Cardizem), verapamil, and verapamil ER (Verelan, Verelan PM) are the main non-DHP CCBs.
DHP CCBs are typically used for managing hypertension. One way to remember medications belonging to this group is that they end in “-dipine.” For instance:
Amlodipine (Norvasc, Katerzia)
Levamlodipine (Conjupri)
Nifedipine ER (Procardia XL)
Nisoldipine (Sular)
Nimodipine (Nymalize)
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2. Calcium channel blockers need some time to kick in
CCBs generally start working 1 to 4 hours after taking your first dose. But the time they need to actually make a difference can be longer. It can take up to 2 to 4 weeks to feel the full benefits of your CCB. The exact amount of time will be based on which CCB you’re prescribed and what you’re taking it for.
Amlodipine, for example, is absorbed more slowly in the body than many other CCBs. It can take about 6 to 12 hours for amlodipine to start working. But it can take up to 4 weeks to see its full effects.
3. There isn’t one best time to take your calcium channel blocker
There isn’t one best time to take CCBs. It boils down to which CCB you’re taking.
For instance, Verelan and Verelan PM are both extended-release (ER) forms of verapamil. But they’re taken at different times of day. You should take Verelan in the morning, but Verelan PM should be taken at bedtime. Verelan PM starts working 4 to 5 hours after you take it, so your early morning blood pressure is better controlled when you take it at night.
You can be more flexible with a medication like amlodipine. You can take it any time that works with your daily routine. The key is to be consistent and take it around the same time each day.
4. Calcium channel blockers last for varying amounts of time
Your medication’s half-life can tell you a lot about how long its effects last.
Amlodipine’s half-life ranges from 30 to 50 hours, which is about how long its effects last. That’s why it’s a once-daily medication. On the other hand, nicardipine’s half-life is about 9 hours. So it’s typically taken 3 times a day.
5. You may need to be mindful of when you eat food with calcium channel blockers
As a general rule, you can take most CCBs with or without food; it’s completely your choice. But there are some exceptions. Some CCBs work better when taken on an empty stomach.
For instance, you should take felodipine ER without food. Taking it with a light meal is OK when needed. But meals that are high in fat or carbohydrates can raise the amount of felodipine in your body, raising the risk of side effects.
Nimodipine and nisoldipine should also be taken on an empty stomach — meaning, at least 1 hour before or 2 hours after a meal. The same goes for diltiazem ER capsules.
Check with your pharmacist about whether food affects your CCB.
6. Missing a dose is natural, but it’s not ideal
It’s natural to occasionally miss a dose of medication. If you forget a dose of your CCB, take it as soon as you remember. But if it’s close to your next dose, skip the missed one and stick to your regular schedule. Never double up on your CCB to make up for a missed dose.
Talk to your pharmacist if you’re frequently having trouble remembering to take your CCB. Pill boxes, medication charts, and GoodRx’s Medicine Cabinet are all tools that can help you successfully stick to a medication routine.
7. Avoiding alcohol is ideal, if possible
Try your best to minimize or avoid drinking alcohol while taking CCBs. Among other effects, alcohol can lead to dizziness and raise your blood pressure. CCBs can also cause dizziness, and the combination can worsen this side effect. Alcohol’s blood pressure effects make it harder for CCBs to do their job, too.
However, non-DHP CCBs clash with alcohol more than DHP CCBs do. Diltiazem and verapamil directly interact with alcohol. Both of these medications make it harder for your body to clear alcohol from the bloodstream. As a result, you may feel stronger effects from alcohol. You may feel intoxicated more easily, and you’re also more likely to experience alcohol poisoning.
Good to know: Drinking alcohol, especially in certain social settings, is ingrained in many U.S. adults. So it’s normal to be tempted to drink while taking a CCB. If you’re having a hard time avoiding alcohol completely, ask your healthcare provider if it’s OK to occasionally consume one to two drinks.
8. There are certain interactions to keep in mind with calcium channel blockers
CCBs interact with certain medications and foods. These interactions may cause new or worsening side effects.
Here are common medications and foods that can interact with CCBs:
Digoxin: Verapamil and diltiazem can increase levels of the heart medication digoxin in the body. If you take digoxin, your dose may need to be lowered if you’re prescribed a CCB.
Certain antibiotics: Erythromycin and clarithromycin can increase CCB levels in your body. This may cause your blood pressure to drop too low. So your healthcare provider may recommend a different antibiotic to take with a CCB.
Cyclosporine: Verapamil, diltiazem, and nicardipine increase levels of cyclosporine, which is taken after an organ transplant, in the body. Your healthcare provider will likely monitor your cyclosporine levels more closely if you’re taking a CCB.
Certain statins: The statins simvastatin and lovastatin interact with amlodipine, verapamil, and diltiazem. This can cause statin levels to increase in the body, which may worsen potential side effects. Your healthcare provider will likely lower your statin dose or recommend a statin that’s less likely to interact with CCBs if you’re taking the combination.
Grapefruit: Grapefruit and grapefruit juice can increase levels of certain CCBs, such as felodipine, in the body. Nicardipine, nimodipine, and nisoldipine are also affected by grapefruit. Use caution with grapefruit products, especially in large quantities, if you’re taking one of these CCBs.
Keep in mind there are other medications not listed above that may interact with CCBs. That’s why it’s a good idea to keep a current list of all of your prescription and OTC medications, including vitamins and supplements. Your pharmacist can check this list to see if any medications interact with your CCB.
9. You can manage side effects from calcium channel blockers
Like all medications, CCBs have some side effects to keep in mind. Many of these side effects improve as your body gets used to the medication.
DHP CCB side effects
Here are some common side effects of DHP CCBs and how to manage them:
Edema (arm or leg swelling): Elevating your legs and wearing compression socks may lower swelling. If these strategies don’t work, other options include lowering your CCB dose or switching to another medication.
Dizziness: When you first start taking a CCB, you may experience dizziness. If you experience this side effect, standing up slowly is important to prevent any falls.
Flushing: Higher doses of CCBs are more likely to cause red or warm skin. The good news is flushed skin should go away once your body adjusts to the CCB.
Fatigue: Feeling tired can make it harder to accomplish your daily activities. Drinking water, eating healthy, and exercising can help improve your energy levels.
Reach out to your pharmacist or healthcare provider if you experience any side effects after you start taking a CCB. And if you have any severe symptoms, such as chest pain or shortness of breath, seek medical care right away.
Non-DHP CCB side effects
Constipation is one of the most common side effects of non-DHP CCBs. Getting plenty of fluids, fitness, and fiber are the top at-home strategies to manage it. If that doesn’t work, OTC laxatives can also help.
Non-DHP CCBs can also cause a low heart rate. People with heart failure and certain types of heart block should avoid taking non-DHP CCBs.
Tips on how to save money on your calcium channel blocker prescription
There are ways to save on your CCB medication. GoodRx can help you navigate your options, which may include GoodRx coupons, copay savings cards, and patient assistance programs. You may be able to find calcium channel blocker prices as low as $10 with a free GoodRx coupon, for example.
The bottom line
Calcium channel blockers (CCBs) are prescription medications that manage high blood pressure and other heart conditions. After you take the first dose, your CCB will typically start working in 1 to 4 hours. But it can take longer to see the full benefits.
CCBs can cause certain side effects, such as swelling from fluid buildup. Your pharmacist can check to see if your CCB interacts with any foods or medications you’re taking to avoid new or worsening side effects.
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References
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