Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
ADALAT CC vs ACULAR PRESERVATIVE FREE
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
Nifedipine, a dihydropyridine calcium channel blocker, inhibits calcium ion influx across cardiac and smooth muscle cell membranes, leading to vasodilation and decreased myocardial contractility.
Ketorolac tromethamine is a nonsteroidal anti-inflammatory drug (NSAID) that inhibits cyclooxygenase (COX-1 and COX-2) enzymes, thereby reducing prostaglandin synthesis. It produces anti-inflammatory and analgesic effects.
Hypertension,Chronic stable angina,Vasospastic angina (Prinzmetal's angina)
FDA-approved: Treatment of ocular inflammation and pain following cataract surgery and corneal refractive surgery.,Off-label: Relief of seasonal allergic conjunctivitis symptoms, management of cystoid macular edema, and treatment of postoperative inflammation in other ocular procedures.
30 mg orally once daily; may titrate to 60 mg or 90 mg once daily based on response and tolerability.
1 drop into affected eye(s) four times daily (every 6 hours). Instill into conjunctival sac. Shake well before use.
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.
Terminal elimination half-life is approximately 5-6 hours in adults, but can be prolonged in elderly patients (up to 8-9 hours) and in patients with renal impairment (up to 13-19 hours).
Hepatic metabolism via CYP3A4; nifedipine is converted to inactive metabolites.
Ketorolac undergoes hepatic metabolism via hydroxylation and conjugation (glucuronidation) to inactive metabolites. It is primarily metabolized by CYP2D6 and CYP3A4 isoenzymes, with renal excretion of metabolites and unchanged drug.
Renal: 70-80% as metabolites, fecal: 15-20% as metabolites, biliary: minimal (<5% unchanged).
Primarily renal excretion of metabolites and unchanged drug; approximately 80% of a dose is excreted in urine as ketorolac and its hydroxy metabolites, with about 6% excreted in feces.
92-98% bound primarily to albumin.
99% bound to plasma proteins, primarily albumin.
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.
0.15-0.25 L/kg after oral administration; for ophthalmic use, systemic absorption is minimal, so Vd is not clinically meaningful.
65-90% after oral administration; absolute bioavailability of nifedipine in ADALAT CC: approximately 65% due to first-pass metabolism in liver and gut wall.
Ophthalmic administration: Systemic bioavailability is approximately 0.5-1% after ocular instillation due to low corneal penetration and rapid clearance; oral bioavailability is 100%.
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.
No dosage adjustment required for renal impairment. Drug is minimally absorbed systemically.
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.
No dosage adjustment required for hepatic impairment. Drug is minimally absorbed systemically.
Safety and efficacy not established; use is not recommended in pediatric patients.
Children ≥3 years: 1 drop into affected eye(s) four times daily. Safety and efficacy in children <3 years not established.
Initiate at 30 mg once daily; titrate slowly due to increased risk of hypotension and higher drug exposure. Monitor closely.
No specific dosage adjustment required. Use same dose as adults; monitor for tolerability.
No FDA black box warning.
NSAIDs may increase the risk of serious cardiovascular events (e.g., myocardial infarction, stroke) and gastrointestinal events (e.g., bleeding, ulceration, perforation). However, due to low systemic absorption with ophthalmic use, this boxed warning is less clinically relevant but still applies.
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
Use with caution in patients with compromised ocular surface, history of herpes simplex keratitis, bleeding tendencies, or those on anticoagulants. Prolonged use may delay wound healing. Monitor for signs of corneal epithelial breakdown or infection.
Hypersensitivity to nifedipine or any component,Cardiogenic shock,Concurrent use with strong CYP3A4 inducers (e.g., rifampin)
Hypersensitivity to ketorolac or any component of the formulation; patients with active ocular infection or advanced dry eye; history of asthma, urticaria, or allergic-type reactions to aspirin or other NSAIDs.
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.
No known food interactions. No dietary restrictions required.
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).
FDA Pregnancy Category C. No adequate studies in pregnant women. In animal studies, ketorolac tromethamine (active ingredient) was not teratogenic in rats or rabbits at doses up to 1.5-3 times the human exposure. However, because NSAIDs can cause premature closure of the ductus arteriosus and oligohydramnios in the third trimester, use is contraindicated after 30 weeks gestation. In first and second trimesters, use only if potential benefit justifies potential fetal risk.
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.
Ketorolac is excreted in human milk following oral administration. After a single intramuscular dose of 10 mg, the milk-to-plasma (M/P) ratio was 0.037. Low levels are expected in breastmilk; however, due to potential adverse effects of NSAIDs on neonates, caution is advised. Use is generally avoided in nursing mothers, especially with premature infants or those with thrombocytopenia or renal impairment.
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.
No specific pharmacokinetic studies in pregnancy. Dosing should be at the lowest effective dose for the shortest duration. Avoid use after 30 weeks gestation. No adjustment for first or second trimester unless renal function changes.
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.
ACULAR (ketorolac tromethamine ophthalmic solution) is an NSAID for ocular use. Preservative-free formulation is indicated for single-use to avoid corneal toxicity. Apply with caution in patients with bleeding disorders or those on anticoagulants due to risk of ocular bleeding. Prolonged use may delay corneal healing. Monitor for signs of keratitis or conjunctival hyperemia.
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.
Use exactly as prescribed; do not touch the dropper tip to any surface to avoid contamination.,Each single-use vial is for one dose only; discard after use to prevent infection.,Remove contact lenses before instillation and wait 10 minutes before reinserting.,Do not drive or operate machinery if vision is blurry after application.,Report eye pain, increased redness, or vision changes to your doctor immediately.
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 ADALAT CC vs ACULAR PRESERVATIVE FREE, answered by our medical review team.
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.. ACULAR PRESERVATIVE FREE is a NSAID Ophthalmic that works by Ketorolac tromethamine is a nonsteroidal anti-inflammatory drug (NSAID) that inhibits cyclooxygenase (COX-1 and COX-2) enzymes, thereby reducing prostaglandin synthesis. It produces anti-inflammatory and analgesic effects.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between ADALAT CC and ACULAR PRESERVATIVE FREE depend on the specific clinical indication. These are agents from distinct pharmacological classes and are not directly interchangeable by dose. A physician or clinical pharmacist should guide any therapeutic switching decisions.
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.. The standard adult dose of ACULAR PRESERVATIVE FREE is: 1 drop into affected eye(s) four times daily (every 6 hours). Instill into conjunctival sac. Shake well before use.. 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 ADALAT CC and ACULAR PRESERVATIVE FREE 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. 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. ACULAR PRESERVATIVE FREE is classified as Category C. FDA Pregnancy Category C. No adequate studies in pregnant women. In animal studies, ketorolac tromethamine (active ingredient) was not teratogenic in rats or rabbits at doses up to. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.