Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
CARDIZEM LA vs ADALAT CC
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
Cardizem LA (diltiazem) is a calcium channel blocker that inhibits calcium ion influx across cardiac and smooth muscle cells during depolarization, leading to negative inotropic, chronotropic, and dromotropic effects. It dilates coronary and peripheral arteries, reducing systemic vascular resistance and myocardial oxygen demand.
Nifedipine, a dihydropyridine calcium channel blocker, inhibits calcium ion influx across cardiac and smooth muscle cell membranes, leading to vasodilation and decreased myocardial contractility.
Hypertension,Chronic stable angina pectoris,Atrial fibrillation or atrial flutter (rate control),Paroxysmal supraventricular tachycardia (PSVT)
Hypertension,Chronic stable angina,Vasospastic angina (Prinzmetal's angina)
Oral, 180-360 mg once daily; initiate at 180 mg once daily, titrate to 240 mg, then 300 mg, then 360 mg once daily as needed.
30 mg orally once daily; may titrate to 60 mg or 90 mg once daily based on response and tolerability.
Terminal elimination half-life: 5-8 hours after oral administration. For extended-release formulations, the half-life is similar but the prolonged absorption phase results in sustained plasma concentrations.
Terminal elimination half-life: 7-10 hours; clinical context: sustained-release formulation provides therapeutic concentrations over 24 hours with once-daily dosing, but half-life does not directly reflect drug effect duration due to slow absorption.
Primarily hepatic via CYP3A4; undergoes extensive first-pass metabolism. Metabolites include N-desmethyl diltiazem (active), deacetyl diltiazem, and others.
Hepatic metabolism via CYP3A4; nifedipine is converted to inactive metabolites.
Urine (2-4% unchanged, ~40% as metabolites); bile/feces (major route, ~60% as metabolites).
Renal: 70-80% as metabolites, fecal: 15-20% as metabolites, biliary: minimal (<5% unchanged).
70-80% bound to plasma proteins (mainly albumin).
92-98% bound primarily to albumin.
3-5 L/kg, indicating extensive tissue distribution.
1.2-1.6 L/kg; clinical meaning: indicates extensive tissue distribution, with higher concentrations in organs such as liver and kidney, and lower in brain due to P-glycoprotein efflux.
Oral: ~40% due to extensive first-pass metabolism; intravenous: 100%.
65-90% after oral administration; absolute bioavailability of nifedipine in ADALAT CC: approximately 65% due to first-pass metabolism in liver and gut wall.
No specific dose adjustment is required for decreased GFR; however, use with caution in severe renal impairment (Cr Cl <30 m L/min) due to potential accumulation.
No dose adjustment required for mild to moderate renal impairment. For severe renal impairment (Cr Cl <30 m L/min), start at 30 mg once daily and titrate cautiously.
Child-Pugh A: no adjustment. Child-Pugh B: reduce dose by 50%. Child-Pugh C: use is not recommended.
For mild to moderate hepatic impairment (Child-Pugh A or B), reduce initial dose to 30 mg once daily; for severe impairment (Child-Pugh C), contraindicated or use with extreme caution.
Safety and efficacy have not been established in pediatric patients; no standard pediatric dosing available.
Safety and efficacy not established; use is not recommended in pediatric patients.
Initiate at low end of dosing range (180 mg once daily) and titrate slowly due to increased risk of hypotension, bradycardia, and reduced hepatic clearance.
Initiate at 30 mg once daily; titrate slowly due to increased risk of hypotension and higher drug exposure. Monitor closely.
None.
No FDA black box warning.
Conduction abnormalities: May worsen sinus node dysfunction or AV block, especially in elderly or with beta-blockers.,Heart failure: Use with caution in patients with reduced left ventricular function.,Hypotension: May cause symptomatic hypotension, especially with concurrent vasodilators.,Hepatic impairment: Diltiazem is hepatically metabolized; use with caution in patients with hepatic impairment.,Abrupt withdrawal: May precipitate angina or hypertension exacerbation; taper dose.,Beta-blocker coadministration: Increased risk of bradycardia, AV block, and hypotension.
Beta-blocker withdrawal: taper if discontinuing; exacerbation of angina,Heart failure: use caution in patients with severe left ventricular dysfunction,Hepatic impairment: reduce dose,Peripheral edema: may occur; differentiate from worsening heart failure,Monitor blood pressure during initiation and titration
Sick sinus syndrome (unless pacemaker present),Second- or third-degree AV block (unless pacemaker present),Systolic blood pressure <90 mm Hg,Acute myocardial infarction with pulmonary congestion,Known hypersensitivity to diltiazem,Concurrent use with rifampin (enzyme inducer reduces effectiveness)
Hypersensitivity to nifedipine or any component,Cardiogenic shock,Concurrent use with strong CYP3A4 inducers (e.g., rifampin)
Avoid grapefruit and grapefruit juice as they inhibit CYP3A4 and may increase diltiazem levels. Limit alcohol intake due to additive vasodilation and hypotension risk. No specific food restrictions otherwise, but maintain a heart-healthy diet low in sodium and saturated fats to support blood pressure and angina management.
Avoid grapefruit and grapefruit juice as they inhibit CYP3A4 metabolism, raising nifedipine levels and risk of toxicity. High-fat meals may increase absorption; take consistently with respect to meals. Avoid alcohol as it may exacerbate hypotension.
Category C. First trimester: No adequate studies in humans; animal studies show embryotoxicity and fetotoxicity at high doses. Second and third trimesters: Risk of fetal bradycardia, hypotension, and growth restriction; avoid use if possible.
Adalat CC (nifedipine) is an extended-release formulation of nifedipine, a dihydropyridine calcium channel blocker. In animal studies, nifedipine has been associated with embryotoxicity, fetotoxicity, and teratogenicity (e.g., digital anomalies, cleft palate) at doses several times the maximum recommended human dose. In humans, data are limited but there is no clear evidence of a significant increase in major congenital malformations. First trimester exposure is not strongly associated with major defects; however, some studies suggest a possible small increase in oral clefts. Second and third trimester use may cause maternal hypotension and subsequent fetal distress (e.g., reduced uteroplacental perfusion). Use near term may theoretically inhibit labor, but nifedipine is used as a tocolytic for preterm labor. Overall, the risk is considered low; however, fetal monitoring is recommended if used in pregnancy. FDA Pregnancy Category C (prior to 2015 categorization).
Diltiazem is excreted in breast milk; M/P ratio not established. Limited data suggest low levels; however, monitor infant for bradycardia, hypotension, and feeding difficulties. Use with caution.
Nifedipine is excreted into human breast milk in small amounts. The milk-to-plasma (M/P) ratio is approximately 0.56 to 1.0 based on limited data. The estimated daily infant dose via milk is less than 5% of the maternal weight-adjusted dose, which is considered clinically insignificant. No adverse effects have been reported in breastfed infants. However, caution is advised, especially with high maternal doses or prolonged use. The American Academy of Pediatrics considers nifedipine compatible with breastfeeding.
No standard dose adjustment; pharmacokinetic changes (increased volume of distribution, altered protein binding) may necessitate titration based on clinical response. Avoid in first trimester if possible.
Pregnancy may alter the pharmacokinetics of nifedipine due to increased plasma volume and altered hepatic metabolism. However, specific dosing adjustments for Adalat CC in pregnancy are not well established. In clinical practice, dosing for hypertension in pregnancy (e.g., preeclampsia) often uses immediate-release nifedipine, not extended-release. For Adalat CC, the same dosing as in non-pregnant adults (30-90 mg once daily) is typically used, but titration should be cautious to avoid maternal hypotension. No formal dose adjustment is recommended, but careful monitoring and individualized titration are advised.
CARDIZEM LA is a once-daily extended-release formulation of diltiazem, a non-dihydropyridine calcium channel blocker. It is useful for hypertension and chronic stable angina. Avoid use in patients with second- or third-degree AV block, sick sinus syndrome without pacemaker, hypotension (SBP <90 mm Hg), or acute MI with pulmonary congestion. Monitor heart rate and PR interval, as it can cause bradycardia and AV block. Contraindicated with IV beta-blockers; caution with oral beta-blockers due to additive negative chronotropic effects. CYP3A4 substrate; avoid strong inhibitors/inducers. Do not crush or chew capsules; can sprinkle contents on applesauce for patients with swallowing difficulties. Max antihypertensive effect may take 2 weeks. Withdrawal may cause angina exacerbation; taper if discontinuing. Use with caution in heart failure with reduced ejection fraction (HFr EF) due to negative inotropic effects.
Adalat CC (nifedipine extended-release) is a dihydropyridine calcium channel blocker used primarily for hypertension. Avoid in patients with unstable angina or within 4 weeks of myocardial infarction due to reflex tachycardia risk. May cause peripheral edema, especially in higher doses; consider adding an ACE inhibitor if edema is problematic. CYP3A4 inhibitors (e.g., grapefruit juice, macrolides, azole antifungals) significantly increase nifedipine levels; avoid coadministration. Tablet shell may appear intact in stool; this is normal.
Take exactly as prescribed, usually once daily. Swallow capsule whole; do not crush or chew. If you have trouble swallowing, you may open the capsule and sprinkle the beads on a spoonful of applesauce; swallow immediately without chewing.,This medication helps lower blood pressure and reduce chest pain (angina). It may take up to 2 weeks to see the full effect on blood pressure. Keep taking it even if you feel well.,Avoid drinking grapefruit juice or eating grapefruit while taking this medication as it can increase side effects.,Common side effects include swelling in legs/ankles, headache, dizziness, or flushing. Report slow heartbeat, severe dizziness, fainting, or shortness of breath to your doctor.,Do not stop taking this medication suddenly, as it may worsen chest pain or cause a heart attack. Your doctor will tell you how to taper the dose if needed.,Limit alcohol consumption, as it may increase dizziness or lower blood pressure further.,Inform all healthcare providers you are taking CARDIZEM LA, especially before surgery or dental procedures.
Swallow the tablet whole; do not crush or chew.,Do not consume grapefruit or grapefruit juice while taking this medication.,May cause dizziness or lightheadedness; avoid driving if affected.,Notify your doctor if you experience rapid heartbeat, swelling in the ankles or feet, or prolonged erections.,Take exactly as prescribed; do not skip doses or stop abruptly without consulting your doctor.
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 CARDIZEM LA vs ADALAT CC, answered by our medical review team.
CARDIZEM LA is a Calcium Channel Blocker that works by Cardizem LA (diltiazem) is a calcium channel blocker that inhibits calcium ion influx across cardiac and smooth muscle cells during depolarization, leading to negative inotropic, chronotropic, and dromotropic effects. It dilates coronary and peripheral arteries, reducing systemic vascular resistance and myocardial oxygen demand.. ADALAT CC is a Calcium Channel Blocker that works by Nifedipine, a dihydropyridine calcium channel blocker, inhibits calcium ion influx across cardiac and smooth muscle cell membranes, leading to vasodilation and decreased myocardial contractility.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between CARDIZEM LA and ADALAT CC 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 CARDIZEM LA is: Oral, 180-360 mg once daily; initiate at 180 mg once daily, titrate to 240 mg, then 300 mg, then 360 mg once daily as needed.. The standard adult dose of ADALAT CC is: 30 mg orally once daily; may titrate to 60 mg or 90 mg once daily based on response and tolerability.. 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 CARDIZEM LA and ADALAT CC 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. CARDIZEM LA is classified as Category C. Category C. First trimester: No adequate studies in humans; animal studies show embryotoxicity and fetotoxicity at high doses. Second and third trimesters: Risk of fetal bradycardi. ADALAT CC is classified as Category C. Adalat CC (nifedipine) is an extended-release formulation of nifedipine, a dihydropyridine calcium channel blocker. In animal studies, nifedipine has been associated with embryotox. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.