Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
ROXICET vs ANEXSIA 7.5/650
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 that inhibits ascending pain pathways and alters pain perception; acetaminophen inhibits cyclooxygenase (COX) enzymes, primarily in the CNS, reducing prostaglandin synthesis and fever.
Management of moderate to severe pain where an opioid analgesic is appropriate
Management of acute pain severe enough to require an opioid analgesic 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 orally every 4 to 6 hours as needed; maximum 6 tablets per day.
Oxycodone: 3-5 hours (immediate-release); prolonged in hepatic/renal impairment. Acetaminophen: 2-3 hours.
Hydrocodone: Terminal half-life 3.8-7.2 hours (mean 5.6 h). Acetaminophen: 1.5-2.5 hours (therapeutic) but prolonged to >4 hours in overdose with hepatotoxicity risk.
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 liver glucuronidation (UGT1A1, UGT1A6, UGT1A9) and sulfation (SULT1A1, SULT1A3), with minor CYP2E1 oxidation.
Primarily renal (90% as glucuronide conjugates, <10% unchanged). Biliary/fecal excretion is minor (<5%).
Hydrocodone: Renal elimination of metabolites (hydromorphone, norhydrocodone) and unchanged drug accounts for ~60-90% of clearance. Acetaminophen: ~85% of dose is excreted in urine as glucuronide and sulfate conjugates; 5-10% unchanged; 2-5% as mercapturate.
Oxycodone: 45-50% (primarily albumin). Acetaminophen: 10-25% (minimal).
Hydrocodone: ~36% bound to serum proteins. Acetaminophen: 10-25% bound (minimal binding).
Oxycodone: 2.6 L/kg; large Vd indicates extensive tissue distribution.
Hydrocodone: Vd ~3-5 L/kg (wide distribution). Acetaminophen: Vd ~0.9-1.0 L/kg (primarily body water).
Oral oxycodone: 60-87%; Acetaminophen: 75-85%.
Oral: Hydrocodone ~70-80% (variable first-pass). Acetaminophen ~63-89% (mean 75-80%).
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.
Cr Cl <30 m L/min: contraindicated; Cr Cl 30-60 m L/min: maximum 3 tablets per day; given the hydrocodone component, avoid in severe renal impairment.
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; Child-Pugh Class B: reduce dose by 50% and monitor; Child-Pugh Class C: contraindicated due to hydrocodone.
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 in pediatric patients due to risk of respiratory depression; for ages <18, contraindicated.
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 with lowest effective dose, monitor for respiratory depression and constipation; maximum 4 tablets per day in patients >65 years.
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.
Risk of addiction, abuse, and misuse; life-threatening respiratory depression; accidental ingestion (especially in children) can be fatal; neonatal opioid withdrawal syndrome; cytochrome P450 3A4 interaction (concomitant use with CYP3A4 inhibitors may increase hydrocodone levels); risk of medication errors (confusion between different strengths).
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.
Addiction, abuse, and misuse; respiratory depression; neonatal opioid withdrawal syndrome; interactions with CNS depressants; risk of serotonin syndrome with serotonergic drugs; adrenal insufficiency; hypotension; seizures; gastrointestinal obstruction; severe cutaneous reactions (acetaminophen); hepatotoxicity (acetaminophen overdose); acute abdominal conditions; impaired mental/physical abilities; elderly/debilitated patients; renal/hepatic impairment.
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 (without monitoring or resuscitative equipment); known or suspected gastrointestinal obstruction (including paralytic ileus); hypersensitivity to hydrocodone or acetaminophen; use with 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 due to increased risk of acetaminophen hepatotoxicity and additive CNS depression. Grapefruit juice may increase hydrocodone absorption; consider avoiding. No other significant food interactions.
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. First trimester: Possible increased risk of cardiac defects with oxycodone. Second/third trimester: Chronic use may lead to neonatal opioid withdrawal syndrome; no clear teratogenicity. Acetaminophen is generally safe, but high doses may be hepatotoxic.
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.
Oxycodone: M/P ratio ~0.8-3; present in milk; risk of neonatal sedation. Acetaminophen: M/P ~0.8-1, low risk. Avoid due to oxycodone; consider alternative analgesic.
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 oxycodone in pregnancy may require increased dose; acetaminophen pharmacokinetics unchanged. Adjust based on pain control and withdrawal risk.
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.
Fixed-dose combination of hydrocodone bitartrate (7.5 mg) and acetaminophen (650 mg). Hydrocodone is a schedule II controlled substance with high abuse potential. Acetaminophen hepatotoxicity risk increases above 3 g/day; prescribe no more than 4 doses per day. Monitor for respiratory depression, especially in opioid-naïve patients. Avoid in severe hepatic impairment. Use with caution in patients with COPD, sleep apnea, or concurrent CNS depressants. Consider naloxone co-prescription if high opioid dose or concurrent benzodiazepine use.
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.
Take exactly as prescribed; do not increase dose or frequency.,Do not take with alcohol or other medications containing acetaminophen.,May cause drowsiness or dizziness; avoid driving or operating machinery until effects are known.,Store securely out of reach of children and others; dispose of unused tablets properly.,Seek emergency care for difficulty breathing, severe sedation, or signs of allergic reaction.,Do not abruptly stop after prolonged use; withdrawal symptoms may occur.
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 7.5/650, 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 7.5/650 is a Opioid Analgesic Combination that works by Hydrocodone is a mu-opioid receptor agonist that inhibits ascending pain pathways and alters pain perception; acetaminophen inhibits cyclooxygenase (COX) enzymes, primarily in the CNS, reducing prostaglandin synthesis and fever.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between ROXICET and ANEXSIA 7.5/650 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 7.5/650 is: 1 tablet orally every 4 to 6 hours as needed; maximum 6 tablets 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 ROXICET and ANEXSIA 7.5/650 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 7.5/650 is classified as Category C. FDA Category C. First trimester: Possible increased risk of cardiac defects with oxycodone. Second/third trimester: Chronic use may lead to neonatal opioid withdrawal syndrome; no . Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.