Diltiazem dosage for afib?

Diltiazem is used for rate control in atrial fibrillation. Dosing depends on route (IV for acute control vs. oral for maintenance) and patient factors. Here are general guidelines, but actual dosing should be individualized by a clinician.

1) Intravenous (acute rate control, usually in hospital)
- Initial: 0.25 mg/kg IV bolus over 2 minutes (max about 20 mg).
- If after 15 minutes the rate/conduction is not adequately slowed: give a second bolus of 0.35 mg/kg IV (max about 25 mg).
- If still not adequate: start continuous infusion 10 mg/hour (about 0.25 mg/kg) and titrate every 15–30 minutes (typical max around 15 mg/hour), guided by heart rate and blood pressure.
- Monitor blood pressure, heart rate, and ECG constantly. Stop if hypotension, signs of AV block, or severe bradycardia occur.

2) Oral immediate-release (IR) diltiazem for maintenance/longer-term rate control
- Common starting dose: 30 mg PO every 6 hours.
- May titrate upward (e.g., to 60 mg every 6 hours) if needed and tolerated.
- Typical maximum around 360 mg per day (divided doses).
- These IR tablets are often used when rapid control is not required.

3) Oral sustained-release (SR/LA/CD) diltiazem for maintenance
- Typical starting dose: 180 mg PO once daily.
- May increase to 240 mg daily or up to 360 mg daily (often given as 180 mg to 360 mg once daily, depending on the product).
- Useful for once-daily dosing and smoother blood levels.

Key cautions and considerations
- Not suitable in hypotension, high-grade AV block without a functioning pacemaker, severe heart failure with reduced ejection fraction, or in ill patients with decompensated HF.
- Can interact with other AV nodal blockers (beta-blockers, digoxin, amiodarone) and may cause bradycardia or heart block. Use with caution and under supervision.
- Avoid if the patient has Wolff-Parkinson-White syndrome with Afib (risk of rapid conduction).
- Dose adjustments may be needed in elderly or those with liver impairment; start low and go slow.
- Always follow the product label and clinician guidance; exact dosing can vary by formulation and patient factors.

If you share more specifics (route needed, acute vs. maintenance, age, kidney/liver function, other meds, presence of heart failure), I can tailor the ranges more precisely.