Cardizem (Diltiazem) - Oral

What Is Cardizem?

Cardizem (diltiazem) is an oral prescription medication used to treat high blood pressure and other heart problems. It is part of the drug class called calcium channel blockers. It widens and relaxes blood vessels in the body and heart, which makes it easier for blood flow. The drug also increases oxygen delivery and makes it easier for the heart to pump blood.

Diltiazem is available as a long-acting capsule (Cardizem CD), regular-release tablets (Cardizem), and long-acting tablets (Cardizem LA). The drug is taken by mouth (oral).

What Is Cardizem Used For?

Cardizem (diltiazem) is a prescription drug that is used to treat:

• High blood pressure
• Chronic stable angina (a type of long-term chest pain)
• Certain types of abnormal heartbeats

How to Take Cardizem

Take this drug at the same time of day. Here is how to take each form of the medication.

Regular release tablet:

• Take it before meals and at bedtime.
• You may swallow, crush, break or chew the regular-release tablets. If your tablets are 30 milligrams (mg), do not break or split the pill. The 30mg tablet does not have a line down the middle (scored).
• If the tablet is not scored, do not cut it in half.

Long-acting preparations:

• Take at the same time (morning or night) with or without food.
• Take it with a full glass of water.
• Swallow the tablets whole. Do not break, chew or crush the long-acting tablets and 12-hour capsules.

Some long-acting drugs include Cardizem CD, Cardizem LA, Cartia XT, and Matzim LA.

Storage

Store your medication in a cool, dry place and avoid moisture. Do not store it in a bathroom. Store diltiazem at room temperature at around 77 degrees Fahrenheit and away from light. The medication can temporarily be stored in cool or mildly hot temperatures (59 to 86 degrees Fahrenheit), such as while you are traveling. Keep diltiazem away from children and pets.

Dispose of any unused and expired medications properly. Do not pour them down the drain, sink, or toilet. Ask your pharmacist about the best way to get rid of your medications. Look out for drug take-back programs in your area.

Off-Label Uses

Cardizem is used off-label to treat:

• Migraine
• Irregular heartbeat (atrial fibrillation)
• Chest pain linked with taking cocaine
• Abnormally thick heart muscles (hypertrophic cardiomyopathy)
• Fast and abnormal heart rate (ventricular tachycardia​)
• Extra heartbeats (ventricular premature beats)
• High blood pressure in the lungs) (pulmonary hypertension)
• Abnormally fast and erratic heartbeat (supraventricular tachycardia)

What Are the Side Effects of Cardizem? 

This is not a complete list of side effects, and others may occur. A healthcare provider can advise you on side effects. If you experience other effects, contact your pharmacist or healthcare provider. You may report side effects to the Food and Drug Administration (FDA) at fda.gov/medwatch or 1-800-FDA-1088.

Common Side Effects

There are some possible side effects of Cardizem. Some people taking Cardizem have little to no side effects. If any of these side effects bother you or do not go away, contact your healthcare provider or seek medical help:

• Headache
• Feeling dizzy
• Feeling tired or weak
• Swelling (edema)
• Slow heart rate (bradycardia)

These are only some of the possible side effects of this drug. Call your healthcare provider if you have any concerns about side effects.

Severe Side Effects

If you have any severe side effects, tell your provider right away. Call 911 if you have a medical emergency or if your symptoms feel life-threatening. Serious adverse effects of Cardizem include:

• Signs of an allergic reaction
• Hives
• Wheezing
• Tightness in the chest or throat
• Trouble breathing, swallowing, or talking
• Unusual hoarseness
• Signs of liver problems
• Dark urine
• Feeling tired
• Stomach pain
• Light-colored stools
• Yellow skin or eyes
• Symptoms of heart failure (new or worsening) 
• Swelling in legs or arms
• Shortness of breath
• Big weight gain
• Severe dizziness or passing out
• Slow heartbeat
• Abnormal heartbeat (new or worsening)

Stevens-Johnson syndrome is a severe allergic skin reaction that may occur with diltiazem. It can cause serious health complications that may or may not go away. They can also lead to death. Call your provider right away if you have any of these symptoms while you are taking diltiazem:

• Irritated or red eyes
• Sores in your mouth, throat, nose, or eyes
• Swollen, blistered, red, or peeling skin (with or without fever)

Dosage: How Much of Cardizem Should I Take?

Modifications

The following changes (modifications) should be kept in mind when using Cardizem:

Severe allergic reaction: Avoid using Cardizem if you have a known allergy to it or any of its ingredients. Ask your pharmacist or healthcare provider for a complete list of the ingredients if you're unsure.

Missed Dose

If you miss a dose, take it as soon as you remember. If it is almost time for your next dose, skip the missed dose and return to your usual dosing schedule. Do not double the amount or take extra doses to make up for a missed dose.

Overdose: What Happens If I Use Too Much Cardizem? 

Cardizem overdose symptoms may include low blood pressure, low heart rate, heart block, or heart failure.

Call your provider or the Poison Control Center right away if you or someone else may have taken too much Cardizem. 

If someone collapses or is not breathing after taking diltiazem, call 911 immediately.

Precautions

What Are Reasons I Shouldn't Take Cardizem? 

Do not take Cardizem if you have:

• Heart failure
• Heart attack
• An allergy to the drug or its ingredients
• Been prescribed a beta-blocker (like metoprolol)
• Fluid in your lungs (pulmonary edema)
• Low blood pressure less than 90 mm Hg systolic (hypotension)
• Sick sinus syndrome or heart block (except if you have a functioning pacemaker)

What Other Medications Interact With Cardizem?

Using certain drugs while on Cardizem may cause severe reactions. Do not take diltiazem with:

• Emend (aprepitant)
• Bosulif (bosutinib)
• Uceris (budesonide)
• Dantrium (dantrolene)
• Adriamycin (doxorubicin)
• Relpax (eletriptan)
• Emend (fosaprepitant)
• Truseltiq (infigratinib)
• Corlanor (ivabradine)
• Dayvigo (lemborexant)
• Juxtapid (lomitapide)
• Zokinvy (lonafarnib)
• Caplyta (lumateperone)
• Sular (nisoldipine)
• Orap (pimozide)
• Addyi (flibanserin)

What Medications Are Similar?

Medications similar to Cardizem that can be used to treat high blood pressure and other heart problems are:

• Calan SR (verapamil)
• Bystolic (nebivolol)
• Cozaar (losartan) 

Verapamil, like diltiazem, is a calcium channel blocker that can cause similar side effects. However, nebivolol and losartan are in different drug classes. Nebivolol is a beta-blocker, while losartan is an angiotensin II receptor blocker.

All of these medications are safe and effective, but some work better than others, depending on the case. 

For example, losartan works better than diltiazem to reduce protein in the urine in people with kidney disease. Diltiazem is also more effective than nebivolol in treating people with high blood pressure and angina.

This list includes drugs for high blood pressure and other heart conditions. It is NOT a list of medicines recommended to take with Cardizem. Do not take these drugs together unless your healthcare provider tells you to. If you have any problems, talk to your healthcare provider.

How Can I Stay Healthy While Taking Cardizem?

High blood pressure is a manageable health condition. I left uncontrolled, it may lead to many health complications. To make sure that your blood pressure is always under control:

• Take your medications correctly and routinely.
• Avoid processed and salty foods.
• Check your blood pressure daily.
• Keep a blood pressure diary.
• Avoid drugs that may increase your blood pressure, like ibuprofen and naproxen.
• Always talk to your healthcare provider before your start, adjust or stop any medicine you take.
• Consider asking your provider to refer you to a registered dietitian nutritionist to help you with your diet and exercise routine.