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diltiazem hydrochloride

Adizem (UK), Angitil (UK), Apo-Diltiaz (CA), Apo-Diltiazem (CA), Calcicard (UK), Cardizem, Cardizem CD, Cardizem LA, Cartia XT, Dilacor-XR, Dilcardia (UK), Dilt-CD, Dilt-XR, Diltia XT, Diltzac, Dilzem (UK), Disogram (UK), Gen-Diltiazem (CA), Med-Diltiazem (CA), Novo-Diltazem (CA), Nu-Diltiaz (CA), Optil (UK), Ratio-Diltiazem (CA), Sandoz Diltiazem (CA), Slozem (UK), Taztia XT, Tiazac, Tildiem (UK), Viazem (UK), Zemtard (UK)

Pharmacologic class: Calcium channel blocker

Therapeutic class: Antianginal, antiarrhythmic (class IV), antihypertensive

Pregnancy risk category C


Inhibits calcium from entering myocardial and vascular smooth-muscle cells, thereby depressing myocardial and smooth-muscle contraction and decreasing impulse formation and conduction velocity. As a result, systolic and diastolic pressures decrease.


Capsules (extended-release, sustained-release): 60 mg, 90 mg, 120 mg, 180 mg, 240 mg, 300 mg, 360 mg, 420 mg

Injection: 5 mg/ml in 10-ml vials, 100-mg Monovial

Tablets: 30 mg, 60 mg, 90 mg, 120 mg

Indications and dosages

Angina pectoris and vasospastic (Prinzmetal's) angina; hypertension; supraventricular tachyarrhythmias; atrial flutter or fibrillation

Adults: 30 to 90 mg P.O. three to four times daily (tablets), or 60 to 120 mg P.O. b.i.d. (sustained-release), or 180 to 240 mg P.O. once daily (extended-release), adjusted after 14 days as needed, up to a total daily dosage of 360 mg. Or 0.25 mg/kg by I.V. bolus over 2 minutes; if response is inadequate after 15 minutes, may give 0.35 mg/kg over 2 minutes; may follow with continuous I.V. infusion at 10 mg/hour (at a range of 5 to 15 mg/hour) for up to 24 hours.

Dosage adjustment

• Severe hepatic or renal impairment
• Elderly patients

Off-label uses

• Unstable angina, coronary artery bypass graft surgery
• Tardive dyskinesia
• Migraine
• Hyperthyroidism
• Raynaud's phenomenon


• Hypersensitivity to drug
• Atrial flutter or fibrillation associated with shortened refractory period (Wolff-Parkinson-White syndrome, with I.V. use)
• Recent myocardial infarction or pulmonary congestion
• Cardiogenic shock, concurrent I.V. beta-blocker therapy, ventricular tachycardia, neonates (with I.V. use, because of benzyl alcohol in syringe formulation)
• Sick sinus syndrome, second- or third-degree atrioventricular block (except in patients with ventricular pacemakers)
• Hypotension (systolic pressure below 90 mm Hg)


Use cautiously in:
• severe hepatic or renal impairment, heart failure
• history of serious ventricular arrhythmias
• concurrent use of I.V. diltiazem and I.V. beta blockers
• elderly patients
• pregnant or breastfeeding patients
• children (safety not established).


• When giving I.V., dilute in dextrose 5% in water or normal saline solution.
• Give I.V. bolus dose over 2 minutes; a second bolus may be given after 15 minutes.
• Administer continuous I.V. infusion at a rate of 5 to 15 mg/hour.

When giving by continuous I.V. infusion, make sure emergency equipment is available and that patient has continuous ECG monitoring with frequent blood pressure monitoring.
• Don't crush tablets or sustained-release capsules; they must be swallowed whole.
• Withhold dose if systolic blood pressure falls below 90 mm Hg, diastolic pressure is below 60 mm Hg, or apical pulse is slower than 60 beats/minute.

Adverse reactions

CNS: headache, abnormal dreams, anxiety, confusion, dizziness, drowsiness, nervousness, psychiatric disturbances, asthenia, paresthesia, syncope, tremor

CV: peripheral edema, bradycardia, chest pain, hypotension, palpitations, tachycardia, arrhythmias, heart failure

EENT: blurred vision, tinnitus, epistaxis

GI: nausea, vomiting, diarrhea, constipation, dyspepsia, dry mouth

GU: urinary frequency, dysuria, nocturia, polyuria, gynecomastia, sexual dysfunction

Hematologic: anemia, leukopenia, thrombocytopenia

Metabolic: hyperglycemia

Musculoskeletal: joint stiffness, muscle cramps

Respiratory: cough, dyspnea

Skin: rash, dermatitis, flushing, diaphoresis, photosensitivity, pruritus, urticaria, erythema multiforme

Other: unpleasant taste, gingival hyperplasia, weight gain, decreased appetite, Stevens-Johnson syndrome


Drug-drug.Beta-adrenergic blockers, digoxin, disopyramide, phenytoin: bradycardia, conduction defects, heart failure

Carbamazepine, cyclosporine, quinidine: decreased diltiazem metabolism, increased risk of toxicity

Cimetidine, ranitidine: increased blood level and effects of diltiazem

Fentanyl, nitrates, other antihypertensives, quinidine: additive hypotension

HMG-CoA reductase inhibitors, imipramine, sirolimus, tacrolimus: increased blood levels of these drugs

Lithium: decreased lithium blood level, reduced antimanic control

Nonsteroidal anti-inflammatory drugs: decreased antihypertensive effect of diltiazem

Theophylline: increased theophylline effects

Drug-diagnostic tests.Hepatic enzymes: increased levels

Drug-food.Grapefruit juice: increased blood level and effects of diltiazem

Drug-behaviors.Acute alcohol ingestion: additive hypotension

Patient monitoring

• Check blood pressure and ECG before starting therapy, and monitor closely during dosage adjustment period. Withhold dose if systolic pressure is below 90 mm Hg.

Monitor for signs and symptoms of heart failure and worsening arrhythmias.
• Supervise patient during ambulation.

Patient teaching

• Instruct patient to swallow extended-release capsules whole and not to crush or chew them.
• Advise patient to change position slowly to minimize light-headedness and dizziness.
• Caution patient to avoid driving and other hazardous activities until he knows how drug affects concentration and alertness.
• As appropriate, review all other significant and life-threatening adverse reactions and interactions, especially those related to the drugs, tests, foods, and behaviors mentioned above.


A trademark for the drug diltiazem hydrochloride.


a trademark for a calcium channel blocker (diltiazem).


Diltiazem, see there.
References in periodicals archive ?
Actions were filed in 11 states and the District of Columbia under state antitrust and related laws, by consumers and health insurers who were indirect purchasers of Cardizem CD and unable to use the federal Sherman Act antitrust laws.
The delay in the availability of the generic form of Cardizem CD meant that consumers, medical insurance companies and the government were forced to purchase the higher priced brand name version of the drug for at least an extra year.
Corbett said the 2003 settlement resolves claims that beginning in July 1998 Hoechst, one of the world's largest pharmaceutical companies, acquired by Aventis in 2000, along with Andrx illegally agreed that Andrx would stay out of the market and not produce a less expensive generic version of Cardizem CD.
Chao, PhD, chairman and chief executive officer of Watson Pharmaceuticals, said, " Rhone-Poulenc Rorer's intent, through its successor, Aventis, to sell Cardizem CD, a product which competes with our Dilacor XR product and its generic equivalent, violates Rhone-Poulenc Rorer's agreements with Watson.
Consumers are being reimbursed for overpayments made for Cardizem CD and its generic equivalents between 1998 and 2004.
The Michigan Attorney General's office alleged that Aventis and Andrx illegally agreed that Andrx would stay off the market with a less expensive generic version of the drug Cardizem CD in return for Aventis paying Andrx nearly $90 million.
The state Attorneys General alleged that Aventis and Andryx illegally agreed that Andryx would stay off the market with a less expensive generic version of the drug Cardizem CD in return for Aventis paying Andryx nearly $90 million.
According to the suit, Aventis (at that time Hoechst) paid Andrx $89 million not to market its generic version of Cardizem CD so that it could continue to make more than $700 million per year in sales of the drug.
Under the terms of a Manufacturing and Supply Agreement, Aventis will continue to manufacture the Cardizem products under contract with Biovail for a specified period.
It reinforces the Cardizem CD product line, which was already available in the strengths of 120, 180, 240 and 300 mg.
charging the companies with conspiring to keep any generic competitor to Hoechst's leading hypertension medication, Cardizem CD, from coming to market.
Through defendant Gerson Lehrman, defendants and those with whom they were working in concert went so far as to pay doctors to provide quotes to the financial press falsely implying that Biovail had implemented a program to bribe doctors to prescribe Cardizem LA.