Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
ANEXSIA 5/325 vs ALTABAX
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
Hydrocodone is a semi-synthetic opioid agonist that binds to mu-opioid receptors in the CNS, inhibiting ascending pain pathways and altering pain perception. Acetaminophen is a para-aminophenol derivative with analgesic and antipyretic effects, primarily through central COX-2 inhibition and activation of descending serotonergic pathways.
Retapamulin is a pleuromutilin antibiotic that selectively inhibits bacterial protein synthesis by interacting with the 50S ribosomal subunit, specifically at the L3 ribosomal protein and the peptidyl transferase center, thereby preventing peptide bond formation.
Management of moderate to moderately severe pain where an opioid analgesic is appropriate
FDA-approved for topical treatment of impetigo due to Staphylococcus aureus and Streptococcus pyogenes in patients aged 9 months and older
1-2 tablets orally every 4-6 hours as needed for pain; maximum 8 tablets per day.
1% ointment applied topically to affected area twice daily for 5 days. Total treatment area should not exceed 100 cm². Maximum single dose is 0.5 g per 100 cm².
Oxycodone: terminal half-life 3.2-4.3 hours (immediate-release); prolonged in hepatic impairment. Acetaminophen: terminal half-life 2-3 hours (therapeutic doses); prolonged in hepatic impairment or overdose.
Terminal half-life is approximately 11-14 hours in adults after topical application, supporting twice-daily dosing.
Hydrocodone: primarily hepatic via CYP3A4 and CYP2D6 to active metabolites (hydromorphone). Acetaminophen: hepatic metabolism via conjugation (glucuronidation, sulfation) and CYP2E1-mediated oxidation to toxic NAPQI.
Retapamulin undergoes hepatic metabolism primarily via cytochrome P450 (CYP) isoenzymes, including CYP3A4, and is excreted in feces and urine.
Oxycodone: renal excretion of metabolites (conjugated and unconjugated) and parent drug; ~10% excreted unchanged. Acetaminophen: renal excretion of metabolites (glucuronide and sulfate conjugates); ~2-4% excreted unchanged.
Retapamulin is primarily eliminated via the fecal route (96.5% of dose), with minimal renal excretion (<0.5% of dose).
Oxycodone: 38-45% bound to albumin and alpha-1-acid glycoprotein. Acetaminophen: 10-25% bound to albumin at therapeutic concentrations.
Retapamulin is approximately 94% bound to human plasma proteins, primarily albumin.
Oxycodone: Vd 2.0-3.0 L/kg; distributes extensively into tissues. Acetaminophen: Vd 0.8-1.0 L/kg; relatively uniform distribution.
Volume of distribution after IV administration is approximately 3.1 L/kg, indicating extensive tissue distribution.
Oxycodone: oral bioavailability 60-87% (immediate-release). Acetaminophen: oral bioavailability 88-98% (therapeutic doses).
Systemic bioavailability after topical application is low and highly variable, with mean values <2% in adults.
GFR 30-50 m L/min: use with caution, increase dosing interval to every 6 hours; GFR <30 m L/min: avoid use due to hydrocodeone accumulation.
No dose adjustment required for renal impairment as systemic absorption is negligible.
Child-Pugh A: no adjustment; Child-Pugh B: reduce dose by 50% and monitor; Child-Pugh C: contraindicated.
No dose adjustment required for hepatic impairment as systemic absorption is negligible.
Not recommended for children under 18 years due to risk of respiratory depression.
Children 9 months and older: Apply 1% ointment to affected area twice daily for 5 days. Maximum treatment area 100 cm². For children under 9 months: safety and efficacy not established.
Start with lowest dose (1 tablet every 6 hours), monitor renal and hepatic function, and avoid in frail elderly due to increased fall and cognitive impairment risk.
No specific dose adjustment required. Use same as adult dosing due to minimal systemic absorption.
Risk of addiction, abuse, and misuse; life-threatening respiratory depression; accidental ingestion; neonatal opioid withdrawal syndrome; risks from concomitant use with benzodiazepines or other CNS depressants; and hepatotoxicity from acetaminophen overdose.
No black box warnings.
Risk of opioid 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; adrenal insufficiency; severe hypotension; gastrointestinal obstruction; seizure; and serotonin syndrome.
Not for use on mucous membranes (e.g., eyes, mouth, vagina).,May cause application site reactions (e.g., pruritus, erythema, pain).,Clostridium difficile-associated diarrhea (CDAD) has been reported with nearly all antibacterial agents, including retapamulin.,Prolonged use may result in overgrowth of nonsusceptible organisms.
Hypersensitivity to hydrocodone or acetaminophen; significant respiratory depression; acute or severe bronchial asthma; GI obstruction; known or suspected paralytic ileus; severe hepatic impairment; and concurrent use of MAOIs within 14 days.
Hypersensitivity to retapamulin or any component of the formulation.
Avoid alcohol. Grapefruit juice may enhance side effects; limit intake. Take with food to reduce gastrointestinal discomfort.
None known. Topical application with negligible systemic absorption; no dietary restrictions.
First trimester: Associated with increased risk of neural tube defects and cardiovascular malformations; avoid use. Second and third trimesters: Chronic exposure may cause fetal renal toxicity, oligohydramnios, and premature closure of ductus arteriosus. Use only if clearly needed.
No adequate and well-controlled studies in pregnant women. Animal studies: oral doses up to 50 mg/kg/day in rats (0.8 times MRHD based on AUC) and 40 mg/kg/day in rabbits (1.6 times MRHD) showed no fetal harm. However, systemic absorption after topical application is minimal, so fetal exposure is negligible. Risk cannot be ruled out; classify as pregnancy category B.
Paracetamol and hydrocodone are excreted in breast milk. M/P ratio: paracetamol ~1.0, hydrocodone ~1.0-2.0. Use with caution; monitor infant for drowsiness and respiratory depression. Consider risk of infant sedation with long-term use.
Not known if retapamulin is excreted in human milk. Systemic absorption is negligible after topical use, so risk to infant is likely low. M/P ratio not determined. Caution if applied to breast area to avoid infant ingestion.
Increased clearance in pregnancy may require dose adjustment. Monitor for pain control and adverse effects; no fixed dose change recommended. Consider lower starting dose due to potential fetal risks. Avoid chronic use; taper if possible.
No dose adjustment needed. Pharmacokinetics unchanged as systemic absorption is minimal (<1%) and not affected by pregnancy. Standard dosing: apply thin layer to affected area twice daily for 5 days.
ANEXSIA 5/325 contains hydrocodone 5 mg and acetaminophen 325 mg. Maximum acetaminophen dose from all sources should not exceed 4 g/day in adults; avoid in severe hepatic impairment. Hydrocodone is a Schedule II controlled substance with abuse potential; monitor for respiratory depression, especially in opioid-naive patients. Use with caution in patients with COPD, sleep apnea, or increased intracranial pressure. Consider naloxone co-prescription for high-risk patients. For acute pain, limit duration to 3-7 days.
Retapamulin (Altabax) is a topical pleuromutilin antibiotic indicated for impetigo due to S. aureus or S. pyogenes. Apply to lesions twice daily for 5 days. Avoid contact with eyes, mouth, or mucous membranes. No systemic absorption significant; safe for use in children ≥9 months. Do not use on open wounds or burns. Monitor for local irritation; discontinue if hypersensitivity occurs.
Take exactly as prescribed; do not increase dose or frequency without consulting your doctor.,Do not consume alcohol or other sedatives (e.g., benzodiazepines) while taking this medication.,Avoid other products containing acetaminophen (e.g., Tylenol, cold remedies) to prevent liver damage.,This medication may cause drowsiness or dizziness; do not drive or operate machinery until you know how it affects you.,Store securely out of reach of others; dispose of unused medication via drug take-back programs.,Seek emergency help if you have trouble breathing, severe drowsiness, or signs of allergic reaction.
Apply a thin layer to the affected area twice daily for 5 days, even if symptoms improve.,Wash hands before and after application unless treating hand lesions.,Do not cover the area with bandages unless instructed by your doctor.,Avoid getting the ointment in your eyes, nose, mouth, or on vaginal area.,Stop use and inform your doctor if you develop severe irritation, redness, or swelling.,Store at room temperature away from heat and moisture.
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 ANEXSIA 5/325 vs ALTABAX, answered by our medical review team.
ANEXSIA 5/325 is a Opioid Analgesic Combination that works by Hydrocodone is a semi-synthetic opioid agonist that binds to mu-opioid receptors in the CNS, inhibiting ascending pain pathways and altering pain perception. Acetaminophen is a para-aminophenol derivative with analgesic and antipyretic effects, primarily through central COX-2 inhibition and activation of descending serotonergic pathways.. ALTABAX is a Topical Antibiotic that works by Retapamulin is a pleuromutilin antibiotic that selectively inhibits bacterial protein synthesis by interacting with the 50S ribosomal subunit, specifically at the L3 ribosomal protein and the peptidyl transferase center, thereby preventing peptide bond formation.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between ANEXSIA 5/325 and ALTABAX 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 ANEXSIA 5/325 is: 1-2 tablets orally every 4-6 hours as needed for pain; maximum 8 tablets per day.. The standard adult dose of ALTABAX is: 1% ointment applied topically to affected area twice daily for 5 days. Total treatment area should not exceed 100 cm². Maximum single dose is 0.5 g per 100 cm².. 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 ANEXSIA 5/325 and ALTABAX 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. ANEXSIA 5/325 is classified as Category C. First trimester: Associated with increased risk of neural tube defects and cardiovascular malformations; avoid use. Second and third trimesters: Chronic exposure may cause fetal re. ALTABAX is classified as Category C. No adequate and well-controlled studies in pregnant women. Animal studies: oral doses up to 50 mg/kg/day in rats (0.8 times MRHD based on AUC) and 40 mg/kg/day in rabbits (1.6 time. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.