DILTIAZEM

“Cardizem”

1) Action

• Calcium antagonist; slow channel blocker

2) Mechanism

• Inhibits influx of calcium ions during membrane depolarisation of cardiac and vascular smooth muscle

• Reduces myocardial oxygen demand [Reduces afterload and heart rate]while increasing myocardial oxygen supply [Dilates coronary arteries] thereby reducing angina

3) Indications

• Angina

• Supraventricular tachyarrhythmias

4) Effects on organs—side effects

• Hypertension

• Bradycardia

5) Toxic effects/ precautions with administration

• Caution when used with beta-blockers

6) Contraindications

• Hypotension

• Heart blocks

• Severe heart failure

7) Reversal, antagonism or antidote

• Atropine for bradycardia

• Vasopressors for hypotension

• Inotropes for cardiac failure

8) Loading dose, maintenance dose, frequency & method of administration

• Orally

9) Drug’s metabolism—Drug’s excretion—Half life (pharmacokinetics)

• Plasma elimination half life: 3.5 hrs

• % plasma protein bound: 70 - 80