Table I.
Dosing Information for Calcium Channel Blockers Currently Marketed in the United States
| Drug | Approved Indications | Form, Strength, and Dose | Time to Peak Effect | Elimination Half‐Life | Comments |
| Amlodipine (Norvasc®) | Hypertension; chronic stable and vasospastic angina | Tablet: 2.5, 5.0, 10 mg once daily | 6–12 h | 30–50 h | No effect of grapefruit juice on pharmacokinetics; available as a fixed‐dose combination with benazepril |
| Bepridil (Vascor®) | Refractory angina | Tablet: 200, 300, 400 mg once daily | 2–3 h | 26–64 h | Can cause torsade de pointes‐type ventricular tachycardia |
| Diltiazem (Tiazac®) (Cardizem®) | Hypertension; chronic stable and vasospastic angina; atrial fibrillation or flutter; paroxysmal SVT | Immediate‐ and sustained‐release: 80–480 mg once daily | 0.5–1.5 h immediate) 6–11 h (sustained) | 2–5 h 2.5 h | Contraindicated in patients with sick‐sinus syndrome and 2nd‐ or 3rd‐degree atrioventricular block |
| Felodipine (Plendil®) | Hypertension | Sustained‐release: 2.5, 5.0, 10.0 mg once daily | 2.5–5.0 h | 11–16h | Grapefruit juice causes a two‐fold or more ↑ in felodipine bioavailability; metabolized by CYP3A4; available as a fixed‐dose combination with enalapril |
| Isradipine (Dynacirc®) | Hypertension | Tablet: 2.5, 5.0 mg twice daily | 1.5 h | 8–12 h | Sustained‐release form in development |
| Nicardipine (Cardene®) | Hypertension; angina | Immediate‐release tablet: 20–40 mg three times daily sustained‐release tablet: 60–120 mg once daily | 0.5–2.0 h | 8h 8h | Available in intravenous form for hypertension treatment |
| Nifedipine (Adalat®) (Procardia®) (Procardia‐XL) | Hypertension; angina ® | Immediate‐release capsule: 10, 20 mg (dose varies by indication); sustained‐release capsule: 30, 60, 90 mg once daily | 0.5 h | 2h | Immediate‐release capsule should not be used for control of essential hypertension or acute reduction of blood pressure |
| Nimodipine (Nimotop®) | Subarachnoid hemorrhage | Capsule: 60 mg every 4 h for 21 days | 1h | 1–2 h | Crosses the blood‐brain barrier readily; oral therapy should commence within 96 h of hemorrhage |
| Nisoldipine (Sular®) | Hypertension | Sustained‐release tablet: 10, 20, 30, 40 mg once daily | 6–12 h | 7–12 h | Grapefruit juice significantly ↑ nisoldipine bioavailability |
| Verapamil (Calan®) (Calan‐SR®) (Covera‐HS®) | Hypertension; angina; atrial fibrillation or flutter; | Immediate‐release tablet: dose varies by indication; sustained release | 0.5–1.0 h | 4.5–12 h | Nocturnally indicated forms of verapamil available |
| (Verelan PM®) | paroxysmal SVT | tablet: 120–480 mg/day | 4–6 h | 4.5–12 h | |
| CYP3A4=cytochrome P3A4; SVT=supraventricular tachycardia; AV=atrioventricular Adapted with permission from N Engl J Med. 1999;341:1447–1457. 1 | |||||