Cardizem CD

Clinical summary

Indications and usage INDICATIONS AND USAGE CARDIZEM CD is indicated for the treatment of hypertension. It may be used alone or in combination with other antihypertensive medications. CARDIZEM CD is indicated for the management of chronic stable angina and angina due to coronary artery spasm. Dosage and administration DOSAGE AND ADMINISTRATION Patients controlled on diltiazem alone or in combination with other medications may be switched to CARDIZEM CD capsules at the nearest equivalent total daily dose. Higher doses of CARDIZEM CD may be needed in some patients. Monitor patients closely. Subsequent titration to higher or lower doses may be necessary. There is limited general clinical experience with doses above 360 mg, but doses to 540 mg have been studied in clinical trials. The incidence of side effects increases as the dose increases with first-degree AV block, dizziness, and sinus bradycardia bearing the strongest relationship to dose. Hypertension: Adjust dosage to individual patient needs. When used as monotherapy, reasonable starting doses are 180 to 240 mg once daily, although some patients may respond to lower doses. Maximum antihypertensive effect is usually observed by 14 days of chronic therapy; therefore, schedule dosage adjustments accordingly. The usual dosage range studied in clinical trials was 240 to 360 mg once daily. Individual patients may respond to higher doses of up to 480 mg once daily. Angina: Dosages for the treatment of angina should be adjusted to each patient’s needs, starting with a dose of 120 or 180 mg once daily. Individual patients may respond to higher doses of up to 480 mg once daily. When necessary, titration may be carried out over a 7- to 14-day period. Concomitant Use with Other Cardiovascular Agents : Sublingual NTG : May be taken as required to abort acute anginal attacks during diltiazem hydrochloride therapy. Prophylactic Nitrate Therapy : Diltiazem hydrochloride may be safely coadministered with short- and long-acting nitrates. Beta-blockers : (see WARNINGS and PRECAUTIONS .) Antihypertensives: Diltiazem hydrochloride has an additive antihypertensive effect when used with other antihypertensive agents. Therefore, the dosage of diltiazem hydrochloride or the concomitant antihypertensives may need to be adjusted when adding one to the other. Warnings and cautions WARNINGS Cardiac Conduction: Diltiazem hydrochloride prolongs AV node refractory periods without significantly prolonging sinus node recovery time, except in patients with sick sinus syndrome. This effect may rarely result in abnormally slow heart rates (particularly in patients with sick sinus syndrome) or second- or third-degree AV block (13 of 3290 patients or 0.40%). Concomitant use of diltiazem with beta-blockers or digitalis may result in additive effects on cardiac conduction. A patient with Prinzmetal’s angina developed periods of asystole (2 to 5 seconds) after a single dose of 60 mg of diltiazem (see ADVERSE REACTIONS ). Congestive Heart Failure: Although diltiazem has a negative inotropic effect in isolated animal tissue preparations, hemodynamic studies in humans with normal ventricular function have not shown a reduction in cardiac index nor consistent negative effects on contractility (dP/dt). An acute study of oral diltiazem in patients with impaired ventricular function (ejection fraction 24% ± 6%) showed improvement in indices of ventricular function without significant decrease in contractile function (dP/dt). Worsening of congestive heart failure has been reported in patients with preexisting impairment of ventricular function. Experience with the use of diltiazem hydrochloride in combination with beta-blockers in patients with impaired ventricular function is limited. Caution should be exercised when using this combination. Hypotension: Decreases in blood pressure associated with diltiazem hydrochloride therapy may occasionally result in symptomatic hypotension. Acute Hepatic Injury: Mild elevations of transaminases with and without concomitant elevation in alkaline phosphatase and bilirubin have been observed in clinical studies. Such elevations were usually transient and frequently resolved even with continued diltiazem treatment. In rare instances, significant elevations in enzymes such as alkaline phosphatase, LDH, SGOT, SGPT, and other phenomena consistent with acute hepatic injury have been noted. These reactions tended to occur early after therapy initiation (1 to 8 weeks) and have been reversible upon discontinuation of drug therapy. The relationship to diltiazem hydrochloride is uncertain in some cases, but probable in some (see PRECAUTIONS ). Drug interactions Drug Interactions Because of the potential for additive effects, slow titration is warranted in patients receiving diltiazem hydrochloride concomitantly with other agents known to affect cardiac contractility and/or conduction (see WARNINGS ). Pharmacologic studies indicate that there may be additive effects in prol