Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
ROXICET vs ANEXSIA 7.5/325
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
Roxicet is a combination of oxycodone, a full mu-opioid receptor agonist, and acetaminophen, which inhibits cyclooxygenase (COX) enzymes, primarily in the central nervous system, to reduce pain perception and fever.
Hydrocodone is a mu-opioid receptor agonist, producing analgesia and euphoria. Acetaminophen inhibits cyclooxygenase (COX) enzymes, reducing prostaglandin synthesis and providing analgesic and antipyretic effects.
Management of moderate to severe pain where an opioid analgesic is appropriate
Management of moderate to moderately severe pain where treatment with an opioid is appropriate and for which alternative treatments are inadequate
1-2 tablets (oxycodone 5-10 mg/acetaminophen 325-650 mg) orally every 4-6 hours as needed for pain; maximum acetaminophen 4000 mg/day (3000 mg/day in high-risk patients).
1 tablet (hydrocodone 7.5 mg / acetaminophen 325 mg) orally every 4 to 6 hours as needed for pain; maximum 6 tablets per day (hydrocodone 45 mg / acetaminophen 1950 mg).
Oxycodone: 3-5 hours (immediate-release); prolonged in hepatic/renal impairment. Acetaminophen: 2-3 hours.
Hydrocodone: 3.8-4.5 hours (immediate-release). Acetaminophen: 2-3 hours. Clinical note: Half-life prolonged in hepatic impairment; requires dose adjustment.
Oxycodone is primarily metabolized by CYP3A4 and to a lesser extent by CYP2D6; acetaminophen is metabolized via conjugation (glucuronidation and sulfation) and by CYP2E1 (minor, but produces toxic NAPQI).
Hydrocodone: CYP3A4 and CYP2D6; Acetaminophen: primarily via glucuronidation (UGT1A1, UGT1A6, UGT1A9) and sulfation, with minor oxidation by CYP2E1.
Primarily renal (90% as glucuronide conjugates, <10% unchanged). Biliary/fecal excretion is minor (<5%).
Renal: ~90-100% as hydrocodone metabolites (conjugated) and unchanged hydrocodone; ~60% as acetaminophen metabolites (glucuronide, sulfate, cysteine); <5% unchanged acetaminophen. Biliary/fecal: <5%.
Oxycodone: 45-50% (primarily albumin). Acetaminophen: 10-25% (minimal).
Hydrocodone: ~20-30% (albumin). Acetaminophen: ~10-25% (albumin).
Oxycodone: 2.6 L/kg; large Vd indicates extensive tissue distribution.
Hydrocodone: 3-4 L/kg (extensive tissue distribution). Acetaminophen: ~1 L/kg (uniformly distributed).
Oral oxycodone: 60-87%; Acetaminophen: 75-85%.
Oral: Hydrocodone ~70% (high first-pass metabolism); Acetaminophen ~85-90% (minimal first-pass).
e GFR 30-60 m L/min: reduce dose to 50-75% of usual. e GFR 10-29 m L/min: reduce dose to 25-50% of usual. e GFR <10 m L/min: avoid use or use with extreme caution; reduce dose to 25% and extend dosing interval to every 8-12 hours.
For GFR 30-59 m L/min: administer every 6 hours; maximum 4 tablets per day. For GFR 15-29 m L/min: administer every 8 hours; maximum 3 tablets per day. For GFR <15 m L/min: not recommended due to accumulation of metabolites.
Child-Pugh Class A: no adjustment necessary. Child-Pugh Class B: reduce starting dose by 50% (e.g., oxycodone 2.5-5 mg) and monitor. Child-Pugh Class C: avoid use or use with extreme caution; reduce dose to 25% and extend interval.
Child-Pugh Class A: no adjustment necessary. Child-Pugh Class B: reduce dose by 25-50% and extend dosing interval to every 6-8 hours; maximum 4 tablets per day. Child-Pugh Class C: contraindicated due to risk of hepatotoxicity.
Weight-based: oxycodone 0.05-0.15 mg/kg per dose, acetaminophen 10-15 mg/kg per dose, orally every 4-6 hours as needed; maximum acetaminophen 75 mg/kg/day (not to exceed 4000 mg/day) in children ≥12 years; for children <12 years, max acetaminophen 75 mg/kg/day (max 325 mg per dose in children <6 years).
Not recommended for pediatric patients; safety and efficacy not established for children under 18 years. For adolescents ≥18 years: adult dosing.
Start with lowest available dose (oxycodone 2.5-5 mg); consider extended dosing interval (every 6-8 hours); monitor renal and hepatic function; avoid in patients with advanced liver disease or GFR <30 m L/min.
Initiate at 1 tablet (hydrocodone 5 mg / acetaminophen 325 mg) every 6 hours as needed; titrate cautiously due to increased sensitivity, decreased renal function, and risk of respiratory depression. Maximum 4 tablets per day.
Addiction, abuse, and misuse; life-threatening respiratory depression; accidental ingestion; neonatal opioid withdrawal syndrome; risks from concomitant use with benzodiazepines or other CNS depressants; hepatotoxicity associated with acetaminophen.
Addiction, abuse, and misuse; life-threatening respiratory depression; accidental ingestion; neonatal opioid withdrawal syndrome; risks from concomitant use with benzodiazepines or other CNS depressants; hepatotoxicity due to acetaminophen.
Respiratory depression; increased intracranial pressure; severe hypotension; hepatotoxicity (acetaminophen); opioid-induced hyperalgesia; adrenal insufficiency; severe hypotension; risks of use in patients with gastrointestinal obstruction; seizures; severe renal impairment.
Risk of opioid addiction, abuse, and misuse; life-threatening respiratory depression; accidental ingestion; neonatal opioid withdrawal syndrome; risks from concomitant use of alcohol, benzodiazepines, or other CNS depressants; hepatotoxicity; severe hypotension; adrenal insufficiency; seizures; GI obstruction; impaired mental/physical abilities; use in elderly, cachectic, or debilitated patients; renal impairment; hepatic impairment; pregnancy; labor and delivery; nursing mothers; pediatric use; driving and operating machinery.
Significant respiratory depression; acute or severe bronchial asthma; known hypersensitivity to oxycodone, acetaminophen, or any component; suspected or known gastrointestinal obstruction (e.g., paralytic ileus); severe hepatic impairment.
Significant respiratory depression; acute or severe bronchial asthma; known or suspected GI obstruction; hypersensitivity to hydrocodone or acetaminophen; concomitant use of MAOIs or within 14 days of such therapy.
Avoid alcohol consumption as it increases the risk of hepatotoxicity from acetaminophen and enhances CNS depression from oxycodone. Grapefruit juice may potentiate oxycodone effects by inhibiting CYP3A4 metabolism; avoid concurrent use. High-fat meals may delay absorption of oxycodone but no specific food restrictions otherwise.
Avoid alcohol consumption due to increased risk of acetaminophen hepatotoxicity and CNS depression. No specific food restrictions, but grapefruit juice may theoretically affect hydrocodone metabolism via CYP3A4 inhibition; however, clinical significance is uncertain.
Pregnancy Category D (FDA). First trimester: Risk of neural tube defects and congenital anomalies with chronic use; no adequate studies. Second trimester: Continued risk of fetal dependence and withdrawal; growth restriction possible. Third trimester: High risk of neonatal opioid withdrawal syndrome (NOWS), respiratory depression, and preterm birth; avoid prolonged use.
FDA Category C (hydrocodone) and Category D (acetaminophen) in third trimester. First trimester: Acetaminophen associated with rare gastroschisis; hydrocodone risk of neural tube defects. Second trimester: No major malformations except with prolonged opioid use. Third trimester: Acetaminophen safe; hydrocodone risk of neonatal opioid withdrawal syndrome (NOWS). Avoid near term.
Oxycodone is excreted into breast milk; M/P ratio ~3.4 (for oxycodone). Relative infant dose 1.7-6.8% of maternal weight-adjusted dose; may cause infant sedation, respiratory depression, and withdrawal. Use with caution, monitor infant for somnolence and feeding difficulties; avoid if mother is on high doses or has CYP2D6 ultra-rapid metabolizer status.
Hydrocodone/acetaminophen excreted in breast milk. M/P ratio unknown. Hydrocodone relative infant dose <3% of weight-adjusted maternal dose. Acetaminophen relative infant dose <2%. Use with caution; monitor infant for sedation, apnea, poor feeding. Highest risk in CYP2D6 ultrarapid metabolizers.
Increased hepatic clearance and volume of distribution in pregnancy may require dose adjustments. No specific guidelines; consider using lowest effective dose and short-term therapy. Taper if discontinuing to prevent withdrawal. Avoid in labor due to neonatal respiratory depression; reserve for severe pain.
Increased clearance of hydrocodone in pregnancy may require dose adjustment; monitor for inadequate analgesia. Acetaminophen pharmacokinetics unchanged. Avoid high doses (hepatotoxicity risk). Consider baseline hepatic function. No specific dose adjustment recommended; titrate to effect.
ROXICET contains oxycodone (an opioid agonist) and acetaminophen. Always assess pain severity and opioid tolerance before prescribing. Monitor for respiratory depression, especially in opioid-naive patients. The maximum daily acetaminophen dose is 4 g (consider hepatic impairment and alcohol use). Avoid concurrent use of other acetaminophen-containing products. Prescribe naloxone for patients at risk of overdose. Use with caution in elderly, renal impairment, and respiratory conditions.
ANEXSIA 7.5/325 (hydrocodone/acetaminophen) carries a boxed warning for acetaminophen hepatotoxicity; maximum acetaminophen dose from all sources should not exceed 4 g/day. Hydrocodone is metabolized by CYP2D6 to hydromorphone; ultrarapid metabolizers may experience toxicity. Avoid concurrent use with other CNS depressants including alcohol. Prescribe with caution in patients with renal impairment (hydrocodone accumulation) or hepatic impairment (acetaminophen toxicity). Monitor for signs of respiratory depression, especially at therapy initiation and dose titration. Use the lowest effective dose for the shortest duration.
Take exactly as prescribed; do not increase dose or frequency without consulting your doctor.,This medication can cause drowsiness or dizziness; avoid driving or operating machinery until you know how you react.,Do not consume alcohol or other central nervous system depressants (e.g., benzodiazepines) while taking this medication.,Risk of dependence; do not share this medication with others. Store securely out of reach of children and pets.,Dispose of unused medication via a drug take-back program or mix with unpalatable substances and seal in a plastic bag before discarding.,Contact your doctor if you experience signs of allergic reaction (rash, itching, swelling), severe constipation, nausea/vomiting, or difficulty breathing.,Avoid taking other acetaminophen-containing products; do not exceed 4,000 mg of acetaminophen per day.
Do not exceed 6 tablets per day due to acetaminophen content.,Avoid alcohol while taking this medication.,Do not drive or operate heavy machinery until you know how this medication affects you.,Take exactly as prescribed; do not share with others.,Seek emergency help if you experience difficulty breathing, severe drowsiness, or signs of allergic reaction.,Store securely out of reach of children and dispose of unused medication properly.
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 ROXICET vs ANEXSIA 7.5/325, answered by our medical review team.
ROXICET is a Opioid Analgesic Combination that works by Roxicet is a combination of oxycodone, a full mu-opioid receptor agonist, and acetaminophen, which inhibits cyclooxygenase (COX) enzymes, primarily in the central nervous system, to reduce pain perception and fever.. ANEXSIA 7.5/325 is a Opioid Analgesic Combination that works by Hydrocodone is a mu-opioid receptor agonist, producing analgesia and euphoria. Acetaminophen inhibits cyclooxygenase (COX) enzymes, reducing prostaglandin synthesis and providing analgesic and antipyretic effects.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between ROXICET and ANEXSIA 7.5/325 depend on the specific clinical indication. These are both Opioid Analgesic Combination agents and are not directly interchangeable by dose. A physician or clinical pharmacist should guide any therapeutic switching decisions.
The standard adult dose of ROXICET is: 1-2 tablets (oxycodone 5-10 mg/acetaminophen 325-650 mg) orally every 4-6 hours as needed for pain; maximum acetaminophen 4000 mg/day (3000 mg/day in high-risk patients).. The standard adult dose of ANEXSIA 7.5/325 is: 1 tablet (hydrocodone 7.5 mg / acetaminophen 325 mg) orally every 4 to 6 hours as needed for pain; maximum 6 tablets per day (hydrocodone 45 mg / acetaminophen 1950 mg).. 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 ROXICET and ANEXSIA 7.5/325 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. ROXICET is classified as Category C. Pregnancy Category D (FDA). First trimester: Risk of neural tube defects and congenital anomalies with chronic use; no adequate studies. Second trimester: Continued risk of fetal d. ANEXSIA 7.5/325 is classified as Category C. FDA Category C (hydrocodone) and Category D (acetaminophen) in third trimester. First trimester: Acetaminophen associated with rare gastroschisis; hydrocodone risk of neural tube d. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.