2-(3,4-dimethoxyphenyl)-5-[2-(3,4-dimethoxyphenyl)ethyl-methyl-amino]-2-(1-methylethyl)pentanenitrile

一般劑量為每日120mg~240mg，於早上服用，依投藥8小時後的反應調整劑量。由錠劑轉換成緩是劑型可使用同等劑量。

Distribution：Rapid early distribution phase (t ½ about 4 min).

Metabolism：Rapidly metabolized. Extensive metabolism in the liver with 12 metabolites having been identified, most only in trace amounts. Major metabolites are N- and O-dealkylated products of verapamil.

Elimination：Terminal elimination t ½ is about 2 to 5 h. About 70% of dose is excreted in the urine and 16% more in feces within 5 days. About 3% to 4% is excreted as unchanged drug.

Special Populations
Elderly
Elimination t ½ may be prolonged.

Other antihypertensive agents
Additive hypotension.

Beta-blockers
May result in increased hypotension and adverse effects because of additive depressant effects on myocardial contractility or AV conduction.

Buspirone
Pharmacologic and adverse effects may be increased by verapamil.

Calcium salts
Clinical effects and toxicities of verapamil may be reversed.

Carbamazepine
Increased carbamazepine serum levels.

Cyclosporine
Increased cyclosporine levels may result.

Dofetilide
Risk of life-threatening ventricular arrhythmias, including torsades de pointes, may be increased. Coadministration with verapamil is contraindicated.

Digitalis glycosides
Increased serum digoxin or digitoxin levels may occur.

Disopyramide
Do not use 48 h before or 24 h after verapamil.

Flecainide
May prolong AV conduction.

Nondepolarizing muscle relaxants
Enhanced muscle relaxant effects and prolonged respiratory depression may occur.

Prazosin
Increased prazosin serum levels may result.

Quinidine
Hypotension, bradycardia, ventricular tachycardia, AV block, and pulmonary edema may occur.

Rifampin
Loss of effectiveness of oral verapamil may occur.

Simvastatin
Plasma levels may be elevated by verapamil, increasing the risk of toxicity (eg, rhabdomyolysis).