NISOLDIPINE Drug Interactions: What You Need to Know

Drug Interactions A 30% to 45% increase in AUC and C max of nisoldipine was observed with concomitant administration of cimetidine 400 mg twice daily.

Ranitidine

150 mg twice daily did not interact significantly with nisoldipine (AUC was decreased by 15% to 20%). No pharmacodynamic effects of either histamine H 2 receptor antagonist were observed. CYP3A4 Inhibitors and Inducers Nisoldipine is substrate of CYP3A4 and coadministration of nisoldipine extended-release tablets with any known inducer or inhibitor of CYP3A4 should be avoided in general. Coadministration of phenytoin with a dose bioequivalent to 34 mg nisoldipine extended-release tablets in epileptic patients lowered the nisoldipine plasma concentrations to undetectable levels. Coadministration of nisoldipine extended-release tablets with phenytoin should be avoided and alternative antihypertensive therapy should be considered. Pharmacokinetic interactions between nisoldipine and beta-blockers (atenolol, propranolol) were variable and not significant. Propranolol attenuated the heart rate increase following administration of immediate release nisoldipine. The blood pressure effect of nisoldipine extended-release tablets tended to be greater in patients on atenolol than in patients on no other antihypertensive therapy. Quinidine at 648 mg bid decreased the bioavailability (AUC) of nisoldipine by 26%, but not the peak concentration. Immediate release nisoldipine increased plasma quinidine concentrations by about 20%. This interaction was not accompanied by ECG changes and its clinical significance is not known. No significant interactions were found between nisoldipine and warfarin or digoxin.

CONTRAINDICATIONS Nisoldipine extended-release tablets are contraindicated in patients with known hypersensitivity to dihydropyridine calcium channel blockers.

WARNINGS Increased Angina and/or Myocardial Infarction in Patients with Coronary Artery Disease Rarely, patients, particularly those with severe obstructive coronary artery disease, have developed increased frequency, duration and/or severity of angina, or acute myocardial infarction on starting calcium channel blocker therapy or at the time of dosage increase. The mechanism of this effect has not been established. In controlled studies of nisoldipine extended-release tablets in patients with angina this was seen about 1.5% of the time in patients given nisoldipine, compared with 0.9% in patients given placebo.