Diltiazem Hydrochloride

Diltiazem hydrochloride

Brand Name: Alti-Diltiazem (CAN), Apo-Diltiaz (CAN), Cardizem, Cardizem CD, Cardizem SR, Cartia XT, Dilacor XR, Diltia XT, Gen-Diltiazem (CAN), Novo-Diltiazem (CAN), Nu-Diltiaz (CAN), Tiamate, Tiazac

Pregnancy Category C

Drug classes: Calcium channel-blocker, Antianginal agent, Antihypertensive

 

Therapeutic actions

Inhibits the movement of calcium ions across the membranes of cardiac and arterial muscle cells, resulting in the depression of impulse formation in specialized cardiac pacemaker cells, slowing of the velocity of conduction of the cardiac impulse, depression of myocardial contractility, and dilation of coronary arteries and arterioles and peripheral arterioles; these effects lead to decreased cardiac work, decreased cardiac energy consumption, and in patients with vasospastic (Prinzmetal's) angina, increased delivery of oxygen to myocardial cells.

 

Indications

· Angina pectoris due to coronary artery spasm (Prinzmetal's variant angina)

· Effort-associated angina; chronic stable angina in patients not controlled by beta-adrenergic blockers, nitrates

· Essential hypertension (sustained release)

· Paroxysmal supraventricular tachycardia, atrial fibrillation, atrial flutter (parenteral)

 

Contraindications

· Allergy to diltiazem, impaired hepatic or renal function, sick sinus syndrome, heart block (second or third degree), lactation.

 

 

Adverse effects

Dizziness, light-headedness, headache, asthenia, fatigue, Peripheral edema, hypotension, arrhythmias, bradycardia, AV block, asystole, Flushing, rash, Nausea, hepatic injury, reflux

 

Drug Interactions:

· Increased serum levels and toxicity of cyclosporine if taken concurrently with diltiazem

· Possible depression of myocardial contractility, AV conduction if combined with beta blockers; use caution and monitor patient closely

 

Interaction with Food:

· Decreased metabolism and increased risk of toxic effects if taken with grapefruit juice; avoid this combination

 

Nursing considerations

· Monitor patient carefully (BP, cardiac rhythm, and output) while drug is being titrated to therapeutic dose; dosage may be increased more rapidly in hospitalized patients under close supervision.

· Monitor BP carefully if patient is on concurrent doses of nitrates.

· Monitor cardiac rhythm regularly during stabilization of dosage and periodically during long-term therapy.

· Ensure patient swallows ER and SR preparations whole; do not cut, crush, or chew.