From the Guidelines
The dose of Cardizem (Diltiazem) for atrial fibrillation is 0.25 mg/kg IV bolus over 2 minutes, with a maintenance infusion of 5-10 mg/h, up to 15 mg/h.
Key Points
- The initial dose of Diltiazem for atrial fibrillation can be repeated as needed, with caution advised to avoid hypotension, worsening heart failure, and bradycardia 1.
- The maintenance infusion dose can be titrated to achieve a heart rate that alleviates symptoms while minimizing adverse effects 1.
- It is essential to use Diltiazem with caution in patients with pre-existing ventricular dysfunction, as it can worsen heart failure, and in patients with hepatic or renal dysfunction, as it can accumulate to toxic levels 1.
- Diltiazem should not be used in patients with AV block greater than first degree or SA node dysfunction (in absence of pacemaker), WPW with AF/atrial flutter, hypotension, decompensated systolic HF/LV dysfunction, or in combination with other AV nodal blocking agents 1.
- The European Society of Cardiology guidelines recommend Diltiazem as a rate control therapy in atrial fibrillation, with a dose of 15-25 mg intravenous bolus (repeated as required) and 60 mg 3 times daily up to 360 mg total daily dose (120-360 mg once daily modified release) for long-term oral rate control 1.
From the FDA Drug Label
DOSAGE AND ADMINISTRATION Direct Intravenous Single Injections (Bolus) The initial dose of diltiazem hydrochloride injection should be 0. 25 mg/kg actual body weight as a bolus administered over 2 minutes (20 mg is a reasonable dose for the average patient). If response is inadequate, a second dose may be administered after 15 minutes. The second bolus dose of diltiazem hydrochloride injection should be 0. 35 mg/kg actual body weight administered over 2 minutes (25 mg is a reasonable dose for the average patient). Continuous Intravenous Infusion For continued reduction of the heart rate (up to 24 hours) in patients with atrial fibrillation or atrial flutter, an intravenous infusion of diltiazem hydrochloride injection or diltiazem hydrochloride for injection may be administered... The recommended initial infusion rate of diltiazem hydrochloride injection or diltiazem hydrochloride for injection is 10 mg/h.
The dose of Cardizem (Diltiazem) for atrial fibrillation is:
- Initial bolus dose: 0.25 mg/kg actual body weight (20 mg for the average patient) administered over 2 minutes
- Second bolus dose (if needed): 0.35 mg/kg actual body weight (25 mg for the average patient) administered over 2 minutes
- Continuous infusion: initial rate of 10 mg/h, which may be increased in 5 mg/h increments up to 15 mg/h as needed 2
From the Research
Dose of Cardizem (Diltiazem) for Atrial Fibrillation
The dose of Cardizem (Diltiazem) for atrial fibrillation can vary depending on the patient's condition and the route of administration.
- The recommended starting dose is an intravenous bolus of 0.25 mg/kg over 2 minutes 3.
- A lower dose of diltiazem, such as 0.2 mg/kg, may be effective in controlling rapid atrial fibrillation and reduce the risk of hypotension 3.
- A standard dose of 10 mg may be noninferior to a weight-based dose of 0.2-0.3 mg/kg for the initial treatment of atrial fibrillation with rapid ventricular response 4.
- The median dose of oral diltiazem and intravenous continuous infusion diltiazem at four hours was 30 mg and 10 mg/h, respectively 5.
- Institution-specific data have identified that many patients receiving diltiazem for atrial fibrillation or atrial flutter are given initial doses that exceed the recommended dose by more than 10%, resulting in hypotension in some patients 6.
Routes of Administration
- Intravenous bolus: 0.25 mg/kg over 2 minutes 3
- Oral immediate-release: 30 mg 5
- Intravenous continuous infusion: 10 mg/h 5
- Weight-based dose: 0.2-0.3 mg/kg 4