Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
COMBOGESIC vs COMBOGESIC IV
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
COMBOGESIC (acetaminophen and tramadol) combines a centrally acting analgesic (tramadol) that binds to mu-opioid receptors and inhibits serotonin and norepinephrine reuptake, with an antipyretic (acetaminophen) that inhibits cyclooxygenase (COX) in the CNS.
Combination of acetaminophen (paracetamol) and ibuprofen. Acetaminophen: Weak COX inhibition in CNS, analgesic and antipyretic. Ibuprofen: Non-selective COX-1/COX-2 inhibition, anti-inflammatory, analgesic, antipyretic.
Management of acute pain severe enough to require an opioid analgesic and for which alternative treatments are inadequate in adults
Management of mild to moderate pain,Reduction of fever (acetaminophen component),Off-label: Acute pain relief in various settings
One tablet (acetaminophen 500 mg / tramadol 37.5 mg) orally every 4 to 6 hours as needed for pain, not to exceed 8 tablets per day.
1 vial (1000 mg paracetamol + 60 mg codeine phosphate) IV infusion over 15 minutes, every 4-6 hours as needed, max 4 vials per day.
Acetaminophen: 2-3 hours; Tramadol: 6.3 hours (slow CYP2D6 metabolizers may exceed 12 hours). Clinically, dosing interval adjusted for renal impairment.
Paracetamol: 1.5-3 hours; tramadol: 6 hours (active metabolite M1: 7-9 hours). Clinical context: Extended half-life in hepatic impairment (cirrhosis) and elderly; requires dose adjustment.
Tramadol: primarily metabolized by CYP2D6 and CYP3A4; O-desmethyltramadol (active metabolite) via CYP2D6. Acetaminophen: primarily metabolized by glucuronidation and sulfation in the liver.
Acetaminophen: Hepatic via conjugation (glucuronidation, sulfation) and CYP2E1 (minor) to reactive metabolite NAPQI. Ibuprofen: Hepatic via CYP2C9 and CYP2C8 to inactive metabolites.
Renal excretion of acetaminophen metabolites (glucuronide, sulfate, cysteine, and mercapturate conjugates); 85% total. Tramadol and metabolites: 90% renal, 10% fecal.
Renal: 90% as glucuronide conjugates and unchanged drug for paracetamol; biliary: 10% for paracetamol. For tramadol: renal 90% (unchanged and metabolites), fecal 10%.
Acetaminophen 10-25%; Tramadol 20% bound to albumin.
Paracetamol: 10-25% bound to albumin; tramadol: 20% bound to albumin; active metabolite M1: negligible binding.
Acetaminophen 0.9 L/kg; Tramadol 2.6 L/kg. Reflects extensive tissue distribution.
Paracetamol: 0.9 L/kg; tramadol: 2.7 L/kg (wide distribution into tissues). Clinical meaning: High Vd for tramadol indicates extensive tissue distribution.
Acetaminophen oral ~88%; Tramadol oral ~75% (due to first-pass metabolism).
IV: 100% for both components. Oral: Paracetamol 85-90%; tramadol 75% (first-pass metabolism). Not applicable for IM/SC routes.
For Cr Cl 30-59 m L/min: increase dosing interval to every 12 hours, maximum 4 tablets per day. For Cr Cl <30 m L/min: not recommended. Hemodialysis: administer dose after dialysis session, use with caution.
e GFR 30-50 m L/min: administer every 6 hours; e GFR <30 m L/min: not recommended; dialysis: contraindicated.
Child-Pugh Class A: no adjustment. Child-Pugh Class B: reduce dose by 50% or extend interval; maximum 4 tablets per day. Child-Pugh Class C: contraindicated.
Child-Pugh A: no adjustment; Child-Pugh B: reduce dose by 50% or extend interval; Child-Pugh C: contraindicated.
Not recommended for pediatric use. Safety and efficacy not established in children.
Children >12 years and ≥50 kg: same as adult dose; <12 years or <50 kg: not recommended due to codeine; use alternative analgesic.
Initiate at lowest effective dose; consider extended dosing interval (every 8-12 hours) and monitor for adverse effects, particularly CNS and respiratory depression.
Initiate at lowest effective dose; monitor for respiratory depression and hypotension; consider reduced dose or extended interval due to age-related clearance decline.
Risk of addiction, abuse, and misuse; life-threatening respiratory depression; accidental ingestion; neonatal opioid withdrawal syndrome; risk of medication errors (combining different forms of acetaminophen leading to hepatotoxicity); serious, life-threatening, or fatal respiratory depression may occur when used with benzodiazepines or other CNS depressants.
Risk of severe hepatic injury with acetaminophen; do not exceed maximum daily dose (4 g/day).
Addiction, abuse, and misuse; life-threatening respiratory depression; neonatal opioid withdrawal syndrome; risks from concomitant use with benzodiazepines or other CNS depressants; hepatotoxicity (associated with acetaminophen); seizures; serotonin syndrome; risk of overdose; interactions with MAOIs; CYP2D6 poor metabolizers may have reduced efficacy; risk of anaphylaxis and hypersensitivity.
Hepatotoxicity (acetaminophen overdose), GI bleeding/ulceration (ibuprofen), renal impairment, cardiovascular thrombotic events (ibuprofen), anaphylactic reactions, masking of infection signs.
Hypersensitivity to tramadol, acetaminophen, or any component; significant respiratory depression; acute or severe bronchial asthma in an unmonitored setting or without resuscitative equipment; known or suspected gastrointestinal obstruction, including paralytic ileus; concomitant use of MAOIs or within 14 days of such therapy.
Hypersensitivity to any component, active GI bleeding, severe hepatic impairment, severe renal impairment (Cr Cl <30 m L/min), history of asthma/urticaria with NSAIDs, perioperative pain in CABG surgery.
Avoid alcohol while taking Combogesic, as it increases the risk of liver damage with acetaminophen and gastrointestinal bleeding with ibuprofen. Taking with food may reduce gastric irritation. No specific food restrictions.
Concurrent food intake does not affect IV administration. However, patients should avoid alcohol consumption due to increased risk of hepatotoxicity from paracetamol and gastrointestinal bleeding from ibuprofen. No other specific food interactions are known.
Combogesic contains paracetamol (acetaminophen) and tramadol. Paracetamol: No increased risk of major malformations; first trimester use is generally considered low risk. Second and third trimester: No known fetal toxicity at therapeutic doses. Tramadol: First trimester: Limited data, but no major teratogenicity observed in animal studies; human data insufficient to exclude risk. Second and third trimester: Not associated with structural anomalies; chronic use may lead to fetal dependence and neonatal withdrawal syndrome. At term: Risk of neonatal respiratory depression if used near delivery; tramadol may prolong labor and increase risk of postpartum hemorrhage.
First trimester: Avoid combination acetaminophen/NSAIDs due to potential cardiovascular and neural tube defects with NSAIDs; acetaminophen considered relatively safe but limit use. Second trimester: NSAIDs associated with oligohydramnios and fetal renal effects; acetaminophen safe at therapeutic doses. Third trimester: NSAIDs contraindicated due to risk of premature ductus arteriosus closure, oligohydramnios, and neonatal renal impairment; acetaminophen preferred.
Paracetamol: Excreted into breast milk in small amounts (M/P ratio ~0.23-0.91); considered compatible with breastfeeding. Tramadol: Excreted into breast milk (M/P ratio ~1.5-2.0); relative infant dose ~2.24% of maternal weight-adjusted dose. Monitor infant for sedation and respiratory depression; avoid in women with CYP2D6 ultra-rapid metabolizer status due to increased risk of high morphine levels in breast milk.
Acetaminophen: Low transfer into breast milk, M/P ratio 0.91-1.42; considered compatible with breastfeeding. Ibuprofen (if applicable, assuming NSAID component): M/P ratio 0.01-0.06, very low levels; considered compatible. Avoid NSAIDs if infant has thrombocytopenia or renal impairment. Monitor infant for rash, drowsiness, or gastrointestinal effects.
Paracetamol: No adjustment required; use lowest effective dose for shortest duration. Tramadol: Pregnancy may alter tramadol pharmacokinetics (increased clearance, decreased Cmax); however, no standard dose adjustment is recommended. Use minimal effective dose; avoid sustained-release formulations. Near term: Consider alternative analgesics to minimize neonatal effects.
Acetaminophen: No dose adjustment needed; use lowest effective dose. NSAID component: Avoid in third trimester; if necessary in earlier trimesters, use lowest effective dose for shortest duration. Pharmacokinetic changes (increased plasma volume, enhanced clearance) may require higher acetaminophen dosing but not standardly adjusted; monitor effect.
Combogesic (paracetamol/acetaminophen + ibuprofen) is a fixed-dose combination used for acute pain. Note that the maximum daily dose of acetaminophen is 4000 mg (or lower in hepatic impairment) and ibuprofen 1200 mg (or lower in renal impairment). Avoid concomitant use of other NSAIDs or acetaminophen-containing products. Use with caution in patients with a history of peptic ulcer or bleeding disorders; ibuprofen may increase bleeding risk.
COMBOGESIC IV is a fixed-dose combination of paracetamol (acetaminophen) 1000 mg and ibuprofen 300 mg per 100 m L solution. Administer only as a single intravenous infusion over 15 minutes. Do not administer if the solution contains particulates or is discolored. Avoid use in patients with severe hepatic impairment (Child-Pugh C), severe renal impairment (e GFR <30 m L/min/1.73m²), active peptic ulcer disease, or history of aspirin allergy. Monitor for signs of hepatotoxicity (paracetamol) and renal toxicity (ibuprofen). Contraindicated in patients with severe heart failure (NYHA III/IV) or preoperative CABG surgery. Use lowest effective dose for shortest duration. Not recommended for patients <18 years due to lack of safety data. Contains ibuprofen; risk of serious GI adverse events including bleeding, ulceration, and perforation, especially in elderly. Do not exceed 4 doses (4000 mg paracetamol/1200 mg ibuprofen) per day. Concomitant use of other NSAIDs or paracetamol-containing products is contraindicated.
Do not exceed the recommended dose as it may cause liver damage or kidney problems.,Avoid taking other products containing acetaminophen or NSAIDs (e.g., ibuprofen, naproxen) while using Combogesic.,Take with food or milk to reduce stomach upset.,Report any signs of stomach bleeding (e.g., black/tarry stools, vomiting blood), rash, or swelling.,Do not use for more than 10 days for pain unless directed by a doctor.
This medication is given intravenously and is not for self-administration.,Inform your healthcare provider if you have a history of liver or kidney disease, stomach ulcers, bleeding disorders, heart disease, high blood pressure, or asthma.,Avoid taking any additional acetaminophen (paracetamol) or NSAIDs (e.g., ibuprofen, naproxen) while receiving this medication.,Report any signs of allergic reaction (rash, itching, swelling, difficulty breathing), stomach pain, black or bloody stools, vomiting blood, unusual bruising or bleeding, yellowing of skin or eyes, dark urine, or severe fatigue.,Do not consume alcohol while being treated with this medication; alcohol increases the risk of liver damage and stomach bleeding.,This medication may cause dizziness or drowsiness; avoid driving or operating machinery if affected.,Tell your doctor about all medications you are taking, including prescription, over-the-counter, and herbal products, especially blood thinners (warfarin, aspirin), diuretics, lithium, methotrexate, and ACE inhibitors.,If you are pregnant, planning to become pregnant, or breastfeeding, discuss the risks with your healthcare provider.
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 COMBOGESIC vs COMBOGESIC IV, answered by our medical review team.
COMBOGESIC is a Analgesic Combination (Opioid + Non-Opioid) that works by COMBOGESIC (acetaminophen and tramadol) combines a centrally acting analgesic (tramadol) that binds to mu-opioid receptors and inhibits serotonin and norepinephrine reuptake, with an antipyretic (acetaminophen) that inhibits cyclooxygenase (COX) in the CNS.. COMBOGESIC IV is a Analgesic Combination (Opioid + Non-Opioid) that works by Combination of acetaminophen (paracetamol) and ibuprofen. Acetaminophen: Weak COX inhibition in CNS, analgesic and antipyretic. Ibuprofen: Non-selective COX-1/COX-2 inhibition, anti-inflammatory, analgesic, antipyretic.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between COMBOGESIC and COMBOGESIC IV depend on the specific clinical indication. These are both Analgesic Combination (Opioid + Non-Opioid) agents and are not directly interchangeable by dose. A physician or clinical pharmacist should guide any therapeutic switching decisions.
The standard adult dose of COMBOGESIC is: One tablet (acetaminophen 500 mg / tramadol 37.5 mg) orally every 4 to 6 hours as needed for pain, not to exceed 8 tablets per day.. The standard adult dose of COMBOGESIC IV is: 1 vial (1000 mg paracetamol + 60 mg codeine phosphate) IV infusion over 15 minutes, every 4-6 hours as needed, max 4 vials per 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 COMBOGESIC and COMBOGESIC IV 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. COMBOGESIC is classified as Category C. Combogesic contains paracetamol (acetaminophen) and tramadol. Paracetamol: No increased risk of major malformations; first trimester use is generally considered low risk. Second an. COMBOGESIC IV is classified as Category C. First trimester: Avoid combination acetaminophen/NSAIDs due to potential cardiovascular and neural tube defects with NSAIDs; acetaminophen considered relatively safe but limit use.. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.