Monograph Details

Cardiovascular System > CHF and arrhythmias
CALAN
Manufacturer
Pfizer Labs
Legal Classification
Rx
Pharmacological Class
Calcium channel blocker (diphenylalkylamine).
Generic Name
Verapamil HCl 40mg, 80mg+, 120mg+; tabs; +scored.
Also
CALAN SR
Indications
Control (with digitalis) of ventricular rate in patients with chronic atrial flutter or fibrillation. Prophylaxis of repetitive paroxysmal supraventricular tachycardia (PSVT).
Children
<18yrs: not recommended.
Adults
Digitalized patients with chronic atrial fibrillation: 240mg–320mg/day in 3–4 divided doses. Prophylaxis of PSVT (non-digitalized patients): 240mg–480mg/day in 3–4 divided doses.
Contraindications
Severe left ventricular (LV) dysfunction or LV dysfunction treated with β-blockers. Moderate to severe heart failure. Hypotension. Cardiogenic shock. Sick sinus syndrome, 2nd- or 3rd-degree AV block, unless paced. Atrial flutter or fibrillation and an accessory bypass tract.
Precautions
Control mild heart failure (eg, with digitalis, diuretics). AV conduction or neuromuscular transmission disorders. Hepatic or renal dysfunction. Monitor liver function. Hypertrophic cardiomyopathy. Pregnancy (Cat.C). Nursing mothers: not recommended.
Interactions
Potentiates alcohol, β-blockers, other antihypertensives, digitalis, theophylline, neuromuscular blockers, flecainide, carbamazepine, cyclosporine. Potentiated by grapefruit juice. Avoid disopyramide; quinidine in cardiomyopathy. Potentiated by CYP3A4 inhibitors (eg, erythromycin, ritonavir); antagonized by CYP3A4 inducers (eg, phenobarbital), rifampin. Inhalation anesthetics may potentiate cardiac depression. May increase bleeding with aspirin. Monitor theophylline, lithium.
Adverse Reactions
Constipation, dizziness, nausea, hypotension, headache, edema, CHF, fatigue, dyspnea, bradycardia, AV block, rash, flushing, elevated hepatic enzymes, paralytic ileus.
How Supplied
Tabs 40mg—100
80mg—100, 500, 1000
120mg—100, 1000
Additional Resources
Related Prescribing Note