Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
DILT-CD vs ADALAT
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
Diltiazem inhibits calcium ion influx during depolarization of cardiac and vascular smooth muscle cells, thereby reducing intracellular calcium levels. It decreases sinoatrial and atrioventricular nodal conduction and dilates coronary and peripheral arteries.
Dihydropyridine calcium channel blocker; inhibits calcium ion influx across cardiac and vascular smooth muscle cells, reducing peripheral vascular resistance and blood pressure.
Hypertension,Chronic stable angina,Variant angina,Atrial fibrillation or atrial flutter (rate control),Paroxysmal supraventricular tachycardia
Hypertension,Chronic stable angina,Vasospastic angina (Prinzmetal's angina)
180-360 mg PO once daily (extended-release); 300-540 mg PO once daily for hypertension; 120-480 mg PO once daily for angina; IV: 0.25 mg/kg bolus over 2 min, then 5-15 mg/hr continuous infusion.
10-20 mg orally three times daily; extended-release: 30-60 mg orally once daily; maximum 120 mg/day.
Terminal elimination half-life 7-10 hours; clinically relevant in hepatic impairment (prolonged to 14-20 hours) and in elderly
Terminal elimination half-life: 2-5 hours (immediate-release); 8-14 hours (extended-release). Context: shorter half-life necessitates multiple daily dosing for immediate-release; extended-release allows once-daily dosing.
Hepatic via CYP3A4; undergoes deacetylation and N-demethylation.
Hepatic via CYP3A4; extensive first-pass metabolism; metabolites are inactive.
Renal 2-4% unchanged; extensive hepatic metabolism; 60-70% fecal, 30-40% renal as metabolites
Renal: 70-80% as metabolites; Fecal: 15-20% as metabolites; <1% unchanged in urine
85-90% bound to plasma proteins (primarily albumin and alpha-1-acid glycoprotein)
92-98% bound to plasma proteins (albumin and alpha-1-acid glycoprotein)
3-5 L/kg; large Vd indicates extensive tissue binding, with highest concentrations in liver, lung, and spleen
0.8-1.2 L/kg. Clinical meaning: indicates extensive tissue distribution, consistent with high lipophilicity.
Oral immediate-release: 40-60% (first-pass effect); oral sustained-release: 30-50%; IV: 100%
Oral immediate-release: 45-60% (due to first-pass metabolism); extended-release: 60-85% (due to slower release and reduced first-pass effect).
No dosage adjustment required for mild-moderate renal impairment; use caution and consider dose reduction in severe renal impairment (Cr Cl <30 m L/min) due to potential accumulation.
No dose adjustment required for GFR ≥30 m L/min; for GFR <30 m L/min, use with caution and reduce initial dose by 50%.
Child-Pugh A: no adjustment; Child-Pugh B: reduce dose by 25-50%; Child-Pugh C: contraindicated or use with extreme caution, reduce dose by at least 50%.
Child-Pugh Class A: no adjustment; Class B: reduce dose by 50%; Class C: avoid use or reduce by 75%.
Not FDA-approved for pediatric use; off-label dosing for hypertension: extended-release initial 2.5-5 mg/kg/day PO once daily, max 10 mg/kg/day up to 360 mg daily; for supraventricular tachycardia: IV bolus 0.1-0.3 mg/kg over 2 min, may repeat after 30 min, max 10 mg/dose.
0.25-0.5 mg/kg/dose orally every 6-8 hours; maximum 3 mg/kg/day. Extended-release not recommended.
Start at lower end of dosing range (e.g., 120 mg PO once daily for hypertension); titrate slowly; monitor for hypotension, bradycardia, and constipation; consider reduced initial dose due to altered pharmacokinetics.
Start at 10 mg orally twice daily; titrate slowly due to increased sensitivity and risk of hypotension.
None.
None
May cause bradycardia, heart block, or heart failure exacerbation,Use caution in patients with impaired left ventricular function,May cause hypotension, especially in patients with aortic stenosis,May increase digoxin and cyclosporine levels,Abrupt withdrawal may exacerbate angina,Hepatic impairment may require dose adjustment,Avoid use in patients with sick sinus syndrome or second/third-degree AV block without pacemaker
May cause hypotension, especially in patients on beta-blockers or with poor cardiac reserve,Risk of increased angina and/or myocardial infarction upon initiation or dose increase,Peripheral edema,Stevens-Johnson syndrome and toxic epidermal necrolysis (rare),Hepatic impairment,Exacerbation of angina on withdrawal
Sick sinus syndrome (except with functioning pacemaker),Second- or third-degree AV block (except with pacemaker),Hypotension (systolic <90 mm Hg),Acute myocardial infarction with pulmonary congestion,Known hypersensitivity to diltiazem,Concomitant use with dantrolene (risk of ventricular fibrillation),Concurrent use with ivabradine
Hypersensitivity to nifedipine,Cardiogenic shock,Significant aortic stenosis,Concurrent use with rifampin,Pregnancy (category C)
Avoid grapefruit and grapefruit juice; they inhibit CYP3A4 and increase diltiazem levels, raising risk of toxicity. High-fat meals may increase absorption; take with food to reduce gastrointestinal upset. Alcohol may enhance hypotension and dizziness; limit consumption.
Avoid grapefruit and grapefruit juice; they inhibit CYP3A4 and increase nifedipine serum concentrations, leading to enhanced hypotensive effects and risk of toxicity. Grapefruit interaction persists for 24 hours; separate consumption by at least 4 hours if unavoidable, but preferable to avoid entirely. Avoid alcohol which can increase hypotension. High-fat meals may reduce absorption of extended-release formulations; take consistently with or without food.
DILT-CD is a formulation of diltiazem, a calcium channel blocker. In animal studies, diltiazem has been associated with fetal skeletal abnormalities and reduced fetal weight at high doses. Human data are limited; however, diltiazem is generally avoided in the first trimester due to potential teratogenic effects. In the second and third trimesters, use is cautioned due to risks of maternal hypotension and possible fetal hypoxia. Diltiazem crosses the placenta and may cause fetal bradycardia.
First trimester: Limited human data; animal studies show embryotoxicity. Second/third trimester: May cause fetal hypoxia due to maternal hypotension; risk of preterm labor inhibition. Category C.
Diltiazem is excreted into breast milk in small amounts; the estimated infant dose is approximately 1% of the maternal weight-adjusted dose. The milk-to-plasma ratio (M/P) is reported as 0.5-1.0. Caution is advised due to potential cardiovascular effects in the nursing infant, though limited data suggest low risk. Monitor infant for bradycardia and hypotension.
Excreted in breast milk; M/P ratio ~0.85. Consider risks versus benefits; monitor infant for hypotension.
Pregnancy may increase diltiazem clearance due to expanded plasma volume and enhanced hepatic metabolism. Dose adjustments may be needed to maintain efficacy; however, specific pharmacokinetic studies for DILT-CD are lacking. Generally, use the lowest effective dose and monitor clinical response. Titrate based on maternal blood pressure and heart rate.
No standard dose adjustment; monitor clinical response and blood pressure; may require lower doses due to vasodilation effects.
DILT-CD is a calcium channel blocker (non-dihydropyridine) used for hypertension and angina. It has negative chronotropic and dromotropic effects; avoid in patients with sick sinus syndrome or second/third-degree AV block without a pacemaker. Monitor heart rate and PR interval. May increase digoxin levels; co-administration requires dose adjustment. Contraindicated with IV beta-blockers due to risk of bradycardia and heart failure.
Adalat (nifedipine) is a dihydropyridine calcium channel blocker. Use immediate-release capsules only for hypertensive emergencies, not chronic treatment due to risk of reflex tachycardia and unpredictable hypotension. Extended-release formulations are preferred for stable angina and hypertension. Avoid grapefruit juice as it increases nifedipine levels via CYP3A4 inhibition. Monitor for peripheral edema, gingival hyperplasia, and constipation. Contraindicated in cardiogenic shock, severe aortic stenosis, and within 4 weeks of myocardial infarction.
Take exactly as prescribed; do not crush or chew extended-release capsules.,May cause dizziness or lightheadedness; avoid driving until you know how this medication affects you.,Report slow heartbeat, shortness of breath, or swelling in your ankles or feet.,Limit alcohol intake as it may increase side effects.,Avoid grapefruit and grapefruit juice as they can increase drug levels and side effects.
Swallow extended-release tablets whole; do not crush, chew, or split.,Avoid grapefruit and grapefruit juice while taking this medication.,Report persistent swelling of ankles/feet, gum tenderness or bleeding, or severe dizziness.,Do not stop abruptly; taper under medical supervision to avoid rebound hypertension.,Take at the same time each day; if a dose is missed, skip it if near next dose.,May cause dizziness; avoid driving until you know how it affects you.,Increase fluid and fiber intake to prevent constipation.,Store at room temperature away from light and moisture.
No interactions on record
No interactions on record
Explore head-to-head clinical comparisons of other medications in the same therapeutic classes.
Common clinical questions about DILT-CD vs ADALAT, answered by our medical review team.
DILT-CD is a Calcium Channel Blocker that works by Diltiazem inhibits calcium ion influx during depolarization of cardiac and vascular smooth muscle cells, thereby reducing intracellular calcium levels. It decreases sinoatrial and atrioventricular nodal conduction and dilates coronary and peripheral arteries.. ADALAT is a Calcium Channel Blocker that works by Dihydropyridine calcium channel blocker; inhibits calcium ion influx across cardiac and vascular smooth muscle cells, reducing peripheral vascular resistance and blood pressure.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between DILT-CD and ADALAT depend on the specific clinical indication. These are both Calcium Channel Blocker agents and are not directly interchangeable by dose. A physician or clinical pharmacist should guide any therapeutic switching decisions.
The standard adult dose of DILT-CD is: 180-360 mg PO once daily (extended-release); 300-540 mg PO once daily for hypertension; 120-480 mg PO once daily for angina; IV: 0.25 mg/kg bolus over 2 min, then 5-15 mg/hr continuous infusion.. The standard adult dose of ADALAT is: 10-20 mg orally three times daily; extended-release: 30-60 mg orally once daily; maximum 120 mg/day.. Dosing should always be individualized based on indication, renal and hepatic function, age, and other patient factors.
No direct drug-drug interaction has been formally documented between DILT-CD and ADALAT in current clinical databases. However, individual patient risk factors including other medications, organ function, and comorbidities should always be evaluated by a qualified healthcare provider.
The maternal-fetal safety profiles differ. DILT-CD is classified as Category C. DILT-CD is a formulation of diltiazem, a calcium channel blocker. In animal studies, diltiazem has been associated with fetal skeletal abnormalities and reduced fetal weight at hig. ADALAT is classified as Category C. First trimester: Limited human data; animal studies show embryotoxicity. Second/third trimester: May cause fetal hypoxia due to maternal hypotension; risk of preterm labor inhibiti. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.