Diltiazem
| Drug monograph · NCLEX study reference | |
| Trade names | Cardizem |
|---|---|
| Therapeutic class | Antihypertensive, antianginal, antiarrhythmic |
| Pharmacologic class | Non-dihydropyridine calcium channel blocker |
| Onset / peak / duration | PO onset 30 to 60 minutes; IV onset within minutes; ER lasts 24 hours. |
| Half-life / level | Half-life 3 to 4.5 hours; no routine level. |
| Routes | PO (oral), IV |
| High-alert (ISMP) | IV form warrants extra caution but is not on the core high-alert list |
| Black box warning | None |
| Antidote / reversal | Calcium, atropine for bradycardia, supportive care. |
| Pregnancy / lactation | Use only if clearly needed. |
Nursing pharmacology study reference (NCLEX-style monograph). Numeric values are standard teaching ranges for study and must be verified against current manufacturer labeling before clinical use. This is educational content, not prescribing guidance.
Diltiazem (brand name Cardizem) — Antihypertensive, antianginal, antiarrhythmic; Non-dihydropyridine calcium channel blocker.
Identification
- Therapeutic class: Antihypertensive, antianginal, antiarrhythmic.
- Pharmacologic class: Non-dihydropyridine calcium channel blocker.
Pharmacology
- Mechanism of action: Blocks calcium channels in cardiac and vascular tissue, slowing AV conduction and heart rate while causing vasodilation.
- Onset / peak / duration: PO onset 30 to 60 minutes; IV onset within minutes; ER lasts 24 hours.
- Half-life / therapeutic level: Half-life 3 to 4.5 hours; no routine level.
Clinical use
- Indications: Hypertension, angina, atrial fibrillation/flutter rate control, supraventricular tachycardia.
- Usual dose, route, frequency: ER 120 to 360 mg PO daily; IV bolus then infusion for rate control.
- Maximum dose / adjustments: ER max about 480 mg/day; caution in heart failure and hepatic impairment.
Safety
- Contraindications: Second or third degree heart block without pacemaker, sick sinus syndrome, severe hypotension, systolic heart failure, with IV beta blockers.
- Black box warning: None.
- Interactions: Beta blockers (additive bradycardia and AV block), digoxin, simvastatin (dose limit), CYP3A4 substrates, grapefruit (food).
- Pregnancy / lactation: Use only if clearly needed.
- High-alert: IV form warrants extra caution but is not on the core high-alert list.
Adverse effects
- Common side effects: Bradycardia, edema, dizziness, constipation.
- Serious effects to report: Symptomatic bradycardia, heart block, hypotension, worsening heart failure.
- Antidote / reversal: Calcium, atropine for bradycardia, supportive care.
Nursing process
- Assessment before administration: Heart rate, blood pressure, ECG, signs of heart failure.
- Interventions during therapy: Hold and notify for heart rate below 60; continuous ECG for IV use.
- Monitor: Heart rate, blood pressure, ECG, signs of heart failure.
- Evaluation / expected outcome: Controlled heart rate and blood pressure.
Patient teaching
- Patient teaching: Check pulse; do not stop abruptly.
- Notify provider if: Slow or irregular heartbeat, fainting, shortness of breath, swelling.
- Administration tips: Swallow ER whole; avoid grapefruit.