Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
BACITRACIN-NEOMYCIN-POLYMYXIN vs ACTRON
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
Bacitracin inhibits bacterial cell wall synthesis by interfering with dephosphorylation of the lipid carrier that transports peptidoglycan precursors. Neomycin and polymyxin B are aminoglycoside and polypeptide antibiotics, respectively; neomycin binds to the 30S ribosomal subunit, causing misreading of m RNA and inhibiting protein synthesis, while polymyxin B disrupts bacterial cell membrane integrity by interacting with lipopolysaccharides and phospholipids, leading to increased permeability and cell death.
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.
Treatment of superficial bacterial infections of the skin and mucous membranes (e.g., wounds, burns, impetigo, folliculitis),Prophylaxis of minor skin abrasions and wounds to prevent infection,Off-label: Use in conjunctival irrigation or ophthalmic infections (as combination ophthalmic preparations)
Mild to moderate pain,Fever
Apply topically to affected area 2-5 times daily.
Oral: 400 mg every 4-6 hours as needed for pain; maximum 1200 mg/day.
Bacitracin: 1.5 hours (prolonged in renal impairment); Neomycin: 2-3 hours (accumulates with renal dysfunction); Polymyxin B: 6-9 hours (increased in renal impairment).
Terminal elimination half-life 2-4 hours; prolonged to 6-12 hours in elderly or renal impairment (Cr Cl <30 m L/min).
Not extensively metabolized. Systemic absorption from topical application is minimal; absorbed drug may undergo hepatic metabolism or be excreted renally unchanged.
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.
Bacitracin: primarily renal (>90% unchanged); Neomycin: renal (30-50% unchanged) with non-renal clearance; Polymyxin: renal excretion of parent drug (60-80% unchanged) with some biliary and fecal elimination.
Renal: 90% as unchanged drug; biliary/fecal: 10% as metabolites.
Bacitracin: <10% bound to plasma proteins; Neomycin: 0-30% bound; Polymyxin B: 50-70% bound, primarily to alpha-1-acid glycoprotein and lipoproteins.
>99% bound to albumin.
Bacitracin: 0.3 L/kg (confined to extracellular fluid); Neomycin: 0.2-0.3 L/kg (low tissue penetration except renal cortex); Polymyxin B: 0.7-1.0 L/kg (extensive tissue binding).
0.1-0.2 L/kg; indicates limited extravascular distribution.
Oral: negligible (<1%) for all three components; topical: minimal systemic absorption via intact skin (<0.5%); ophthalmic/otic: minimal absorption via mucosal surfaces.
Oral: 70-90% (first-pass metabolism minimal); IV: 100%.
No systemic absorption; no dosage adjustment required.
GFR <30 m L/min: Avoid use. GFR 30-50 m L/min: Reduce dose to 50% of normal, maximum 600 mg/day.
No systemic absorption; no dosage adjustment required.
Child-Pugh Class B: Reduce dose by 50%; maximum 600 mg/day. Child-Pugh Class C: Contraindicated.
Apply topically to affected area 2-5 times daily; same as adult dose.
Children ≥12 years: 400 mg orally every 6-8 hours as needed; maximum 1200 mg/day. Children <12 years: Not recommended.
Apply topically to affected area 2-5 times daily; same as adult dose.
Initiate at 200 mg every 6-8 hours; maximum 600 mg/day due to increased risk of gastrointestinal bleeding and renal impairment.
Not applicable for topical formulations. However, systemic use of bacitracin (rare) may cause nephrotoxicity and anaphylactic reactions. Neomycin may cause ototoxicity and nephrotoxicity with systemic absorption.
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.
Prolonged use may result in overgrowth of nonsusceptible organisms including fungi.,Topical use may cause allergic contact dermatitis, especially with neomycin.,Avoid application to large areas, open wounds, or damaged skin due to potential systemic absorption and toxicity.,Use with caution in patients with renal impairment or pre-existing hearing loss (neomycin component).,Ototoxicity and nephrotoxicity may occur if significant systemic absorption occurs.
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.
Hypersensitivity to any component (bacitracin, neomycin, polymyxin B) or other aminoglycosides/polypeptide antibiotics.,Ophthalmic use in eyes with corneal abrasions or perforation (relative).,Known history of neomycin-associated ototoxicity or nephrotoxicity.
Severe hepatic impairment or active liver disease. Known hypersensitivity to acetaminophen or any component of the formulation.
No significant food interactions; topical application minimizes systemic absorption. No dietary restrictions.
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.
Bacitracin-Neomycin-Polymyxin is a topical combination with negligible systemic absorption; thus, fetal risk is minimal. No known teratogenic effects reported; animal studies for individual components show no fetal harm at systemic doses. However, neomycin has theoretical risk of ototoxicity if systemically absorbed, but topical use is considered low risk. FDA Pregnancy Category C for components, but topical use deemed safe.
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.
Minimal systemic absorption after topical application; excretion into breast milk is unlikely. M/P ratio not determined; safe for use during breastfeeding if applied to small areas and not to open wounds.
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.
No dosing adjustments necessary for pregnancy. Pharmacokinetic changes due to pregnancy (e.g., increased skin blood flow, hydration) are not clinically significant for this topical combination. Standard topical application is appropriate.
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.
Triple antibiotic ointment (bactiracin-neomycin-polymyxin) is first-line for prophylaxis of minor skin infections; avoid use on large areas, deep wounds, or burns due to risk of systemic absorption and nephrotoxicity. Neomycin carries high risk of allergic contact dermatitis; consider alternative in patients with known hypersensitivity. Topical use only; not for ophthalmic or intranasal application due to polymyxin ocular toxicity. Synergistic coverage includes Gram-positive (bacitracin), Gram-negative (polymyxin), and broad-spectrum (neomycin).
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.
Apply a thin layer to clean, minor cuts, scrapes, or burns 1-3 times daily.,Do not use on large body areas, deep puncture wounds, animal bites, or serious burns.,Stop use and consult doctor if rash, irritation, or signs of infection (worsening redness, swelling, pus) develop.,Avoid use on eyes, nose, or mouth; if contact occurs, rinse thoroughly with water.,Tell your doctor if you have kidney problems or are allergic to any of the ingredients (bacitracin, neomycin, polymyxin B).
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.
"The therapeutic efficacy of Picosulfuric acid can be decreased when used in combination with Bacitracin."
"Bacitracin may increase the nephrotoxic activities of Colistimethate."
"Bacitracin may increase the nephrotoxic activities of Streptomycin."
No interactions on record
Explore head-to-head clinical comparisons of other medications in the same therapeutic classes.
Common clinical questions about BACITRACIN-NEOMYCIN-POLYMYXIN vs ACTRON, answered by our medical review team.
BACITRACIN-NEOMYCIN-POLYMYXIN is a Aminoglycoside Antibiotic that works by Bacitracin inhibits bacterial cell wall synthesis by interfering with dephosphorylation of the lipid carrier that transports peptidoglycan precursors. Neomycin and polymyxin B are aminoglycoside and polypeptide antibiotics, respectively; neomycin binds to the 30S ribosomal subunit, causing misreading of m RNA and inhibiting protein synthesis, while polymyxin B disrupts bacterial cell membrane integrity by interacting with lipopolysaccharides and phospholipids, leading to increased permeability and cell death.. 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.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between BACITRACIN-NEOMYCIN-POLYMYXIN and ACTRON 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 BACITRACIN-NEOMYCIN-POLYMYXIN is: Apply topically to affected area 2-5 times daily.. The standard adult dose of ACTRON is: Oral: 400 mg every 4-6 hours as needed for pain; maximum 1200 mg/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 BACITRACIN-NEOMYCIN-POLYMYXIN and ACTRON 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. BACITRACIN-NEOMYCIN-POLYMYXIN is classified as Category A/B. Bacitracin-Neomycin-Polymyxin is a topical combination with negligible systemic absorption; thus, fetal risk is minimal. No known teratogenic effects reported; animal studies for i. 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. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.