Abstract

Diltiazem is a calcium channel blocker used mainly to treat angina.¹ Two manufacturers have recently introduced longer acting formulations of diltiazem, to be taken twice instead of three times a day. The elimination half-life of the drug ranges between 2 and 11 hours, longer when renal or liver function is impaired. The dosage patients need therefore varies considerably, and must often be titrated. The long acting tablets act for over 12 hours, so that the drug accumulates to reach a steady state in about 3 days.