Drug Reference
Rhythm
Diltiazem
Non-dihydropyridine calcium channel blocker (class IV)
IndicationAdult
Rate controlAdult0.25 mg/kg (≈ 15–20 mg) IV over 2 min; then 0.35 mg/kg after 15 min; infusion 5–15 mg/h
Indications
- AFib / flutter rate control
- SVT after adenosine
Contraindications & cautions
- HFrEF / decompensated HF
- Hypotension / cardiogenic shock
- Pre-excited AFib (WPW)
- Wide-complex tachycardia of unknown origin
Key pearls
- Hypotension is the main adverse effect; calcium can reverse it
- Lower bolus (e.g., 10 mg) is often effective with fewer BP drops