Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
ACTRON vs ACETAMINOPHEN AND IBUPROFEN
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
Acetaminophen (paracetamol) is a non-opioid analgesic and antipyretic. Its mechanism is not fully understood but involves inhibition of cyclooxygenase (COX) enzymes in the central nervous system, reducing prostaglandin synthesis. It also modulates the endocannabinoid system and serotonergic pathways.
Acetaminophen is a centrally acting analgesic and antipyretic whose exact mechanism is not fully understood, but is thought to involve inhibition of cyclooxygenase (COX) in the brain and modulation of cannabinoid receptors. Ibuprofen is a nonsteroidal anti-inflammatory drug (NSAID) that non-selectively inhibits COX-1 and COX-2, reducing prostaglandin synthesis.
Mild to moderate pain,Fever
Temporary relief of minor aches and pains,Reduction of fever,Off-label: Management of osteoarthritis pain, headache, dysmenorrhea
Oral: 400 mg every 4-6 hours as needed for pain; maximum 1200 mg/day.
Oral: Acetaminophen 325 mg and ibuprofen 200 mg, 1-2 tablets every 6 hours as needed, not exceeding 6 tablets/24 hours.
Terminal elimination half-life 2-4 hours; prolonged to 6-12 hours in elderly or renal impairment (Cr Cl <30 m L/min).
Acetaminophen: 2-3 hours (normal hepatic function). Ibuprofen: 2-4 hours (immediate-release); prolonged in overdose or hepatic impairment.
Primarily metabolized in the liver via glucuronidation (UGT1A1, UGT1A6, UGT1A9), sulfation (SULT1A1, SULT1A3), and oxidation (CYP2E1, CYP3A4) to form the toxic metabolite N-acetyl-p-benzoquinone imine (NAPQI), which is detoxified by glutathione.
Acetaminophen is primarily metabolized via glucuronidation and sulfation; a minor pathway via CYP2E1 produces a toxic metabolite, NAPQI. Ibuprofen is metabolized primarily by CYP2C9 and to a lesser extent by CYP2C8.
Renal: 90% as unchanged drug; biliary/fecal: 10% as metabolites.
Acetaminophen: renal excretion of metabolites (glucuronide 55%, sulfate 30%, cysteine/mercapturate <10%); <5% unchanged. Ibuprofen: renal excretion of metabolites (conjugates) 90%; <10% unchanged; minor biliary/fecal.
>99% bound to albumin.
Acetaminophen: 10-25% (albumin). Ibuprofen: >99% (albumin).
0.1-0.2 L/kg; indicates limited extravascular distribution.
Acetaminophen: 0.9 L/kg; Ibuprofen: 0.15 L/kg (highly protein-bound, low Vd).
Oral: 70-90% (first-pass metabolism minimal); IV: 100%.
Acetaminophen: 75-85% oral. Ibuprofen: 80-100% oral.
GFR <30 m L/min: Avoid use. GFR 30-50 m L/min: Reduce dose to 50% of normal, maximum 600 mg/day.
GFR 30-59: Caution, use lowest effective dose; GFR <30: Contraindicated due to ibuprofen component.
Child-Pugh Class B: Reduce dose by 50%; maximum 600 mg/day. Child-Pugh Class C: Contraindicated.
Child-Pugh A: No adjustment; Child-Pugh B: Caution, reduce acetaminophen dose; Child-Pugh C: Contraindicated.
Children ≥12 years: 400 mg orally every 6-8 hours as needed; maximum 1200 mg/day. Children <12 years: Not recommended.
Weight-based: 10-15 mg/kg acetaminophen + 5-10 mg/kg ibuprofen per dose, every 6-8 hours, max 4 doses/day.
Initiate at 200 mg every 6-8 hours; maximum 600 mg/day due to increased risk of gastrointestinal bleeding and renal impairment.
Use lowest effective dose; monitor renal function due to ibuprofen; avoid durations >10 days.
Acetaminophen has been associated with cases of acute liver failure, sometimes resulting in liver transplant and death. Most cases involve use of acetaminophen at doses exceeding 4000 mg per day, often involving more than one acetaminophen-containing product.
Acetaminophen may cause severe liver injury, including acute liver failure, at doses exceeding 4,000 mg/day. Ibuprofen: NSAIDs increase risk of serious cardiovascular thrombotic events, myocardial infarction, and stroke, which can be fatal. Risk increases with duration of use and in patients with cardiovascular risk factors. NSAIDs also increase risk of serious gastrointestinal adverse events including bleeding, ulceration, and perforation of stomach or intestines.
Hepatotoxicity: risk increased with chronic alcohol use, liver disease, or use of other acetaminophen-containing products. Avoid exceeding 4000 mg/day. Severe skin reactions: Stevens-Johnson syndrome, toxic epidermal necrolysis, acute generalized exanthematous pustulosis. Hypersensitivity reactions: anaphylaxis.
Acetaminophen: Hepatotoxicity risk with excessive doses, use with caution in hepatic impairment, avoid with alcohol use >3 drinks/day. Ibuprofen: Cardiovascular risk, gastrointestinal bleeding, renal toxicity, hypertension, fluid retention, avoid late pregnancy.
Severe hepatic impairment or active liver disease. Known hypersensitivity to acetaminophen or any component of the formulation.
Acetaminophen: Severe hepatic impairment, allergy to acetaminophen. Ibuprofen: Hypersensitivity to ibuprofen or other NSAIDs, history of asthma/urticaria after NSAIDs, perioperative pain in CABG surgery, severe heart failure, active GI bleeding, late pregnancy.
Avoid alcohol; may increase risk of GI bleeding. No specific food restrictions, but taking with food can reduce gastrointestinal irritation. Maintain adequate hydration to prevent renal impairment.
Avoid alcohol; take with food or milk to minimize GI irritation. No specific food restrictions.
First trimester: Based on animal studies and limited human data, possible increased risk of cardiovascular and neural tube defects. Second/third trimester: Risk of premature closure of ductus arteriosus and oligohydramnios with prolonged use. Avoid after 30 weeks gestation.
First trimester: Acetaminophen is considered low risk; ibuprofen is associated with increased risk of miscarriage and cardiac defects. Second trimester: Acetaminophen is safe; ibuprofen is relatively safe but may cause oligohydramnios. Third trimester: Acetaminophen is safe; ibuprofen is contraindicated due to risk of premature closure of ductus arteriosus, oligohydramnios, and neonatal renal impairment.
Excreted in breast milk; M/P ratio 0.15. Low oral bioavailability to infant; considered compatible with breastfeeding. Monitor infant for sedation or feeding problems.
Acetaminophen: low levels in breast milk, M/P ratio ~0.9; considered compatible with breastfeeding. Ibuprofen: minimal excretion, M/P ratio ~0.01; considered compatible. Combination: low risk with recommended doses.
Dose adjustment not typically required; however, due to increased renal clearance and volume of distribution in pregnancy, higher doses may be needed to achieve therapeutic effect. Use lowest effective dose for shortest duration.
No standard adjustment for acetaminophen; ibuprofen dosing unchanged in pregnancy but avoid in third trimester; consider increased clearance of acetaminophen in pregnancy but no dose adjustment recommended.
ACTRON (ketorolac tromethamine) is a nonsteroidal anti-inflammatory drug (NSAID) for short-term management of moderate to severe acute pain, typically not exceeding 5 days due to risk of GI bleeding, renal impairment, and cardiovascular events. Avoid in patients with active peptic ulcer disease, bleeding diathesis, or advanced renal disease. Monitor renal function and signs of bleeding. Use lowest effective dose for shortest duration. May cause bronchospasm in aspirin-sensitive asthma.
Combination product for acute pain; fixed-dose may exceed recommended daily acetaminophen limit if other acetaminophen-containing products are used. Onset of ibuprofen is 30-60 min, acetaminophen 15-30 min; duration 4-6 hours. Caution in renal impairment (ibuprofen) and hepatic impairment (acetaminophen). Avoid in third trimester of pregnancy.
Take with food or milk to reduce stomach upset.,Do not take for more than 5 days as prescribed; longer use increases risk of serious side effects.,Avoid alcohol while taking this medication to lower risk of stomach bleeding.,Report any signs of bleeding (e.g., black stools, vomiting blood), unusual bruising, or decreased urination.,Do not take with other NSAIDs (e.g., ibuprofen, naproxen) or aspirin without consulting your doctor.,Inform your doctor about all medications, especially blood thinners (e.g., warfarin) and diuretics.,If you have asthma, be aware of potential bronchospasm; seek immediate help if you have breathing trouble.,Not recommended during pregnancy, especially in the third trimester.
Do not exceed 10 tablets (500 mg acetaminophen/200 mg ibuprofen) per day.,Do not take with other products containing acetaminophen or NSAIDs.,Take with food or milk to reduce stomach upset.,Avoid alcohol while taking this medication.,Seek medical help if pain persists >10 days or fever >3 days.,Store at room temperature, away from moisture.
No interactions on record
"Concomitant use of Ibuprofen (a nonsteroidal anti-inflammatory drug, NSAID) and Methylprednisolone (a systemic corticosteroid) synergistically increases the risk of gastrointestinal (GI) ulceration, bleeding, and perforation due to additive inhibition of prostaglandin synthesis and mucosal protection. Additionally, Ibuprofen may potentiate the immunosuppressive effects of Methylprednisolone, elevating infection risk. This interaction can lead to serious clinical outcomes, including acute GI hemorrhage, perforation, and impaired wound healing."
"The combination of olopatadine, an antihistamine with sedative properties, and ibuprofen, a nonsteroidal anti-inflammatory drug (NSAID), may result in additive central nervous system (CNS) depression, leading to increased sedation, dizziness, and impaired psychomotor function. Ibuprofen can inhibit the metabolism of olopatadine via competition for hepatic CYP450 enzymes, potentially elevating olopatadine plasma concentrations and prolonging its systemic effects. Clinically, patients may experience exacerbated drowsiness, reduced alertness, and increased risk of falls or accidents, especially in the elderly or those with compromised hepatic function."
"Ibuprofen, a nonsteroidal anti-inflammatory drug (NSAID), can decrease the metabolism of pioglitazone, a thiazolidinedione antidiabetic agent, by inhibiting cytochrome P450 2C8 (CYP2C8) enzyme activity. This inhibition elevates plasma concentrations of pioglitazone, potentially enhancing its hypoglycemic effects and increasing the risk of adverse reactions such as edema, weight gain, and heart failure exacerbation. Clinically, concomitant use may lead to improved glycemic control but also raises concerns for dose-dependent toxicities, necessitating careful monitoring and possible dose adjustment of pioglitazone."
Explore head-to-head clinical comparisons of other medications in the same therapeutic classes.
Common clinical questions about ACTRON vs ACETAMINOPHEN AND IBUPROFEN, answered by our medical review team.
ACTRON is a NSAID that works by Acetaminophen (paracetamol) is a non-opioid analgesic and antipyretic. Its mechanism is not fully understood but involves inhibition of cyclooxygenase (COX) enzymes in the central nervous system, reducing prostaglandin synthesis. It also modulates the endocannabinoid system and serotonergic pathways.. ACETAMINOPHEN AND IBUPROFEN is a NSAID that works by Acetaminophen is a centrally acting analgesic and antipyretic whose exact mechanism is not fully understood, but is thought to involve inhibition of cyclooxygenase (COX) in the brain and modulation of cannabinoid receptors. Ibuprofen is a nonsteroidal anti-inflammatory drug (NSAID) that non-selectively inhibits COX-1 and COX-2, reducing prostaglandin synthesis.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between ACTRON and ACETAMINOPHEN AND IBUPROFEN depend on the specific clinical indication. These are both NSAID agents and are not directly interchangeable by dose. A physician or clinical pharmacist should guide any therapeutic switching decisions.
The standard adult dose of ACTRON is: Oral: 400 mg every 4-6 hours as needed for pain; maximum 1200 mg/day.. The standard adult dose of ACETAMINOPHEN AND IBUPROFEN is: Oral: Acetaminophen 325 mg and ibuprofen 200 mg, 1-2 tablets every 6 hours as needed, not exceeding 6 tablets/24 hours.. 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 ACTRON and ACETAMINOPHEN AND IBUPROFEN 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. ACTRON is classified as Category C. First trimester: Based on animal studies and limited human data, possible increased risk of cardiovascular and neural tube defects. Second/third trimester: Risk of premature closur. ACETAMINOPHEN AND IBUPROFEN is classified as Category D/X. First trimester: Acetaminophen is considered low risk; ibuprofen is associated with increased risk of miscarriage and cardiac defects. Second trimester: Acetaminophen is safe; ibup. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.