Diltiazem (Cardizem) works well to treat chest pain caused by poor blood flow to the heart. Unlike its extended-release counterpart that's taken once a day, diltiazem (Cardizem) is taken four times a day. Common side effects of diltiazem (Cardizem) include swelling in the legs, dizziness, and tiredness.
New chest pain
Long-term chest pain
Diltiazem (Cardizem) is a calcium channel blocker that slows your heart rate and relaxes your blood vessels. This gets more oxygen to the heart so it doesn't have to work as hard to pump, which relieves chest pain.
Source:Â FDA
Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor immediately if any of the following side effects occur:
More common
Body aches or pain
congestion
dryness or soreness of the throat
hoarseness
tender or swollen glands in the neck
trouble swallowing
voice changes
Less common
Chest pain or discomfort
chills
difficult or labored breathing
feeling faint, dizzy, or lightheaded
feeling of warmth or heat
flushing or redness of the skin, especially on the face and neck
general feeling of discomfort or illness
headache
joint pain
loss of appetite
muscle aches and pains
shivering
slow or irregular heartbeat
sweating
swelling of the hands, ankles, feet, or lower legs
tightness in the chest
trouble sleeping
unusual tiredness or weakness
vomiting
Incidence not known
Blistering, peeling, or loosening of the skin
large, hive-like swelling on the face, eyelids, lips, tongue, throat, hands, legs, feet, or sex organs
no heartbeat
red skin lesions, often with a purple center
red, irritated eyes
sores, ulcers, or white spots in the mouth or on the lips
Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
Less common
Acid or sour stomach
belching
continuing ringing or buzzing or other unexplained noise in the ears
degenerative disease of the joint
difficulty with moving
hearing loss
indigestion
lack or loss of strength
muscle aching or cramping
muscle pains or stiffness
pain or tenderness around the eyes and cheekbones
rash
stomach discomfort, upset, or pain
swollen joints
Incidence not known
Hair loss or thinning of the hair
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.
Prevents heart-related chest pain (angina) if you take it regularly
Can crush and chew tablets
Available as a lower-cost generic option
Need to take four times a day
Don't take with alcohol
Not for people with certain types of heart failure
Diltiazem (Cardizem) can cause dizziness or fatigue when you first start taking it or when your provider raises your dose. Hold onto something sturdy so that you don't fall when standing up from a seated or lying down position.
Since diltiazem (Cardizem) wears off quickly, take it throughout the day at the same times each day. A good way to remember to take it is to take it before meals (e.g., breakfast, lunch, and dinner) and before bedtime.
You can crush or chew diltiazem (Cardizem) tablets. Make sure, however, that you're actually taking diltiazem (Cardizem) and not the extended-release version of this medication. The extended-release version must be swallowed whole.
Tell your provider and pharmacist about all of the medications that you're taking. Diltiazem (Cardizem) may interact with other medications such as statins (for cholesterol) and blood pressure medications.
Diltiazem (Cardizem) can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
Risk factors: Taking digoxin or beta-blockers at the same time
Rarely, diltiazem (Cardizem) can cause heart rhythm problems. Sometimes, this can lead to abnormally slow heart rate. Your risk of this side effect is higher if you're taking certain medications, such as digoxin or beta-blockers. Let your provider know if you feel weak or lightheaded, these might be symptoms of heart-related problems.
Diltiazem (Cardizem) can cause low blood pressure, especially if you're already taking blood pressure medications. Let your provider know right away if you experience symptoms of low blood pressure, such as dizziness, weakness, confusion, and blurry vision.
Risk factors: History of liver disease
Though very rare, there have been reports of people who developed liver injury within the first 2 weeks of taking diltiazem (Cardizem). Often times, this liver damage was mild and went away on its own in 1-2 months after their provider stopped the medication. If this happens, your provider will likely monitor your liver health with blood tests.
The typical starting dose is 30 mg by mouth 4 times a day before meals and at bedtime. If needed, your provider will raise your dose slowly over time. The typical daily dose ranges from 180 mg to 360 mg, divided into 3 to 4 equal doses, and taken throughout the day.
Using this medicine with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or change some of the other medicines you take.
Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Sick sinus syndrome (except if you have a ventricular pacemaker)
Second- or third-degree AV block (except if you have a ventricular pacemaker)
Uncontrolled hypotension (less than 90 mm Hg systolic)
Active myocardial infarction and pulmonary (lungs) congestion
New chest pain
Long-term chest pain
Chest pain (angina)
Prevention and treatment of certain types of arrhythmias
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Dakkak, W., et al. (2023). Sick sinus syndrome. StatPearls.
Kashou, A. H., et al. (2023). Atrioventricular block. StatPearls.
LiverTox: Clinical and Research Information on Drug-Induced Liver Injury. (2017). Diltiazem. National Institute of Diabetes and Digestive and Kidney Diseases.
ScieGen Pharmaceuticals, Inc. (2023). DILTIAZEM HYDROCHLORIDE tablet DILTIAZEM HYDROCHLORIDE tablet [package insert]. DailyMed.
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