Diltiazem
CARDIZEM
Pronunciation: dil-TYE-a-zem
“Dill ties a Cardigan”
What it isNon-dihydropyridine calcium channel blocker; rate control in atrial fibrillation, angina and hypertension.
Why this oneCompared with verapamil, it causes less constipation and myocardial depression while retaining AV-nodal rate control.
What limits itNegative inotrope: avoid in reduced EF. A moderate CYP3A4 inhibitor, which matters with statins and tacrolimus.
FDA-approved for
- angina (1982)
- hypertension (~1985)
- atrial fibrillation (~1992)
Off-label
- anal fissure (topical)
FDA label
Read the full label on DailyMed ↗
| FDA dosing | Population | Start | Target | Max |
|---|---|---|---|---|
| Chronic stable angina; angina due to coronary artery spasm | Adults | 30 mg QID (before meals and at bedtime) | 180–360 mg/day divided TID–QID | 360 mg/day (usual optimum range upper limit) |
Titration Increase gradually at 1–2 day intervals until optimum response.
Renal Undefined (no dosing data; titrate with particular caution).
Hepatic Undefined (no dosing data; titrate with particular caution).
Instructions
- May be swallowed whole, crushed, or chewed; do not split
- Take before meals and at bedtime
Available strengths
- tab 30, 60, 90, 120 mg
- ER cap 60, 90, 120, 180, 240, 300, 360, 420 mg
- ER tab 120, 180, 240, 300, 360, 420 mg
- inj 5 mg/mL
Contraindications
- Sick sinus syndrome (except with functioning ventricular pacemaker)
- Second- or third-degree AV block (except with functioning ventricular pacemaker)
- Hypotension (systolic <90 mm Hg)
- Acute myocardial infarction with pulmonary congestion on x-ray
Cautions
- Cardiac conduction effects (bradycardia, AV block)
- Congestive heart failure
- Symptomatic hypotension
- Acute hepatic injury (rare)
Adverse reactions
- Edema
- Headache
- Nausea
- Dizziness
- Rash
- Asthenia
Pregnancy Animal embryo/fetal lethality and skeletal abnormalities; use only if potential benefit justifies risk.
Lactation Undefined.
Cost
| Strength | #/mo | generic $/mo | CostPlus | |
|---|---|---|---|---|
| 30 mg | tab | 120 QID | $5.95 | offered |
| 60 mg | tab | 120 QID | $8.57 | offered |
| 90 mg | tab | 120 QID | $8.39 | offered |
| 120 mg | tab | 120 QID | $11.88 | offered |
Other forms: Diltiazem ER (CARDIZEM CD)
Generic entry1992
NO BOXED WARNINGS
Principal riskBradycardia and heart block; a moderate CYP3A4 inhibitor
Classes and tags
Clinical profile
Legacy pregnancy categoryC
Defining liabilityBradycardia, heart block and hypotension; overdose can cause refractory cardiogenic shock.
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