Diltiazem

Diltiazem is a prescription medication used to treat the symptoms of Chest Pain, Hypertension, Paroxysmal Supraventricular Tachycardia, and Atrial Fibrillation or Flutter.

• Diltiazem is available under the following different brand names: Cardizem, Cardizem CD, Cardizem LA, Cartia XT, Dilacor, Dilacor XR, Dilatrate, Diltazem, Diltazem CD, Dilt-CD, Diltia XT, Diltiaz, Diltiaz CD, Diltiaz SR, Diltiazem CD, Diltiazem SR, Dilzem, Taztia XT, Tiazac

Adult dosage

Capsule/tablet, extended release

• 120mg
• 180mg
• 240mg
• 300mg
• 360mg
• 420mg

Injectable solution

• 5mg/mL

Powder for injection

• 100mg

Tablet

• 30mg
• 60mg
• 90mg
• 120mg

Angina

• Conventional: 30 mg orally every 6 hours; increased every 1 or 2 days until anginal controlled (unusually 180-360 mg per day orally divided every 6-8 hours); not to exceed 360 mg per day
• Cardizem CD, Cartia XT, Dilt-CD: 120-180 mg/day orally; titrate over 7-14 days; maintenance range usually 120-320 mg/day; not to exceed 480 mg/day
• DilacorXR, Dilt-XR: 120 mg/day orally; titrate after 7-14 days; maintenance range usually 120-320 mg/day; not to exceed 540 mg/day
• Tiazac, Taztia XT: 120-180 mg/day orally; titrate after 7-14 days; maintenance range usually 120-320 mg/day; not to exceed 540 mg/day
• Cardizem LA, Matzim LA: 180 mg/day orally; titrate after 14 days; maintenance range usually 120-320 mg/day; not to exceed 360 mg/day

Hypertension

• Cardizem CD, Cartia XT, Dilt-CD: 180-240 mg/day orally; titrate after 14 days; maintenance range usually 180-420 mg/day; not to exceed 480 mg/day
• Dilacor XR, Dilt-XR: 180-240 mg/day orally; titrate after 14 days; maintenance range usually 180-420 mg/day; not to exceed 540 mg/day
• Tiazac, Taztia XT: 120-240 mg/day orally; titrate after 14 days; maintenance range usually 180-420 mg/day; not to exceed 540 mg/day
• Cardizem LA, Matzim LA: 180-240 mg/day orally; titrate after 14 days; maintenance range usually 120-540 mg/day
• Extended-release twice-daily dosing: 60-120 mg orally every 12 hours; may be adjusted after 14 days; maintenance range usually 240-360 mg/day

Paroxysmal Supraventricular Tachycardia

• 0.25 mg/kg (average adult dose, 20 mg) direct IV over 2 minutes; after 15 minutes, may repeat bolus by administering 0.35 mg/kg actual body weight over 2 min (average adult dose, 25 mg) direct IV if first dose tolerated but response inadequate; some clinicians suggest additional doses every 15 minutes
• Use weight-based dosing for lower-body-weight patients. 
• Continuous infusion: 10 mg/hr IV initially; increased to no more than 15 mg/hr for up to 24 hours

Atrial Fibrillation/Flutter

• 0.25 mg/kg (usual adult dose, 20 mg) direct IV over 2 minutes; after 15 minutes, may repeat bolus by administering 0.35 mg/kg actual body weight over 2 min (average adult dose, 25 mg) direct IV if first dose tolerated but response inadequate; some clinicians suggest additional doses every 15 minutes  
• Use weight-based dosing for lower-body-weight patients
• Continuous infusion: 10 mg/hr IV initially; increased to no more than 15 mg/hr for up to 24 hours

Pediatric Dosage

• Safety and efficacy not established in children in younger than 18 years of age

Dosage Considerations – Should be Given as Follows: 

• See "Dosages."

Common side effects of Diltiazem include:

• swelling, 
• dizziness, 
• weakness, 
• headache, 
• nausea, and
• rash

Serious side effects of Diltiazem include:

• hives, 
• difficulty breathing, 
• swelling of the face, lips, tongue, or throat, 
• fever, 
• sore throat, 
• burning eyes, 
• skin pain, 
• red or purple skin rash with blistering and peeling, 
• chest pain, 
• slow heartbeats, 
• pounding heartbeats, 
• fluttering in the chest, 
• lightheadedness, 
• swelling, 
• rapid weight gain, and
• shortness of breath

Rare side effects of Diltiazem include:

• none 

This is not a complete list of side effects and other serious side effects or health problems may occur as a result of the use of this drug. Call your doctor for medical advice about serious side effects or adverse reactions. You may report side effects or health problems to FDA at 1-800-FDA-1088.

If your medical doctor is using this medicine to treat your pain, your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them.  Do not start, stop, or change the dosage of any medicine before checking with your doctor, health care provider or pharmacist first

• Diltiazem has severe interactions with the following drugs:
  • dantrolene
  • flibanserin
  • lomitapide
  • lonafarnib
  • pimozide
• Diltiazem has serious interactions with at least 75 other drugs.
• Diltiazem has moderate interactions with at least 261 other drugs.
• Diltiazem has minor interactions with at least 30 other drugs.  

This information does not contain all possible interactions or adverse effects.  Visit the RxList Drug Interaction Checker for any drugs interactions. Therefore, before using this product, tell your doctor or pharmacist of all the products you use.  Keep a list of all your medications with you, and share this information with your doctor and pharmacist.  Check with your health care professional or doctor for additional medical advice, or if you have health questions, concerns.

Contraindications

• Hypersensitivity
• Wolff-Parkinson-White syndrome, Lown-Ganong-Levine syndrome, symptomatic severe hypotension (systolic BP less than 90 mm Hg), sick sinus syndrome (if no pacemaker), 2°/3° (if no pacemaker); heart block
• PO: Acute MI and pulmonary congestion
• IV: Use in newborns (because of benzyl alcohol), concomitant beta-blocker therapy, cardiogenic shock, ventricular tachycardia (must determine whether origin is supraventricular or ventricular)

Effects of drug abuse

• None

Short-Term Effects

• See "What Are Side Effects Associated with Using Diltiazem?"

Long-Term Effects

• See “What Are Side Effects Associated with Using Diltiazem?”

Cautions

• May cause abnormally slow heart rates or second- or third-degree AV block’ patients with sick sinus syndrome are at increased risk of bradycardia (risk increases with agents known to slow cardiac conduction
• Stevens-Johnson syndrome, toxic epidermal necrolysis, erythema multiforme and/or exfoliative dermatitis reported
• Significant elevations in liver enzymes such as alkaline phosphatase, LDH, AST (SGOT), ALT (SGPT) and signs of acute hepatic injury reported; reversible upon discontinuation of drug therapy
• Mild elevations of transaminases with and without concomitant elevation in alkaline phosphatase and bilirubin observed; elevations were usually resolved even with continued diltiazem treatment
• Symptomatic hypotension with or without syncope reported
• Peripheral edema occurs within 2-3 weeks of starting therapy
• Use with caution in hypertrophic obstructive cardiomyopathy, hepatic/renal impairment, left ventricular dysfunction
• Concomitant use of diltiazem with beta-blockers or digitalis may result in additive effects on cardiac conduction; sinus bradycardia resulting in hospitalization reported with concurrent use of clonidine and other agents that slow cardiac conduction
• May increase the risk of adverse cardiac events in patients with heart failure due to negative inotropic effects (risk directly related to the severity of baseline HF)

Pregnancy and Lactation

• Use with caution if benefits outweigh risks during pregnancy.  
• Drug enters breast milk; because of risk for serious adverse reactions in nursing infants from diltiazem, a decision should be made whether to discontinue nursing or to discontinue to drug, taking into account the importance of the drug to the mother.