Diltiazem Dosing for Atrial Fibrillation
Intravenous Diltiazem Dosing
- For acute rate control in atrial fibrillation with rapid ventricular response, administer diltiazem 0.25 mg/kg (actual body weight) IV over 2 minutes, according to the American College of Cardiology 1, 2
- If inadequate response, may repeat with 0.35 mg/kg IV over 2 minutes, as recommended by the American College of Cardiology 1, 2
- Follow with continuous infusion at 5-15 mg/hour for ongoing rate control, as suggested by the American College of Cardiology 1, 2
Oral Diltiazem Dosing
- Oral maintenance dose: 120-360 mg daily of extended-release (ER) formulation, recommended by the American College of Cardiology 1, 2, 3
- Immediate-release formulation has a half-life of 3-4.5 hours, according to the American College of Cardiology 1
- Extended-release formulation has a half-life of 4-9.5 hours, as reported by the American College of Cardiology 1
Important Considerations and Precautions
- Avoid diltiazem in patients with heart failure with reduced ejection fraction (HFrEF), as advised by the American College of Cardiology 1, 2, 3
- Use caution in patients with renal or hepatic impairment, according to the European Heart Journal 5
- Assess heart rate response both at rest and during exercise, as recommended by the European Heart Journal and the American College of Cardiology 5, 6
Alternative Rate Control Options
- Beta blockers (metoprolol, atenolol, esmolol) are alternative first-line agents, according to the American College of Cardiology 1, 2
- Verapamil (another non-dihydropyridine calcium channel blocker) can be used at 5-10 mg IV over ≥2 minutes, with oral maintenance of 180-480 mg daily (ER), as suggested by the American College of Cardiology 1
- Digoxin may be considered in patients with heart failure, with loading dose of 0.25-0.5 mg IV followed by 0.0625-0.25 mg daily maintenance, as recommended by the American College of Cardiology 1
- Diltiazem is primarily used for rate control in atrial fibrillation and does not convert patients back to sinus rhythm, as reported by Circulation 4, 7