Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
BACITRACIN-NEOMYCIN-POLYMYXIN vs BACITRACIN-NEOMYCIN-POLYMYXIN W/ HYDROCORTISONE ACETATE
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.
Bacitracin inhibits bacterial cell wall synthesis by interfering with dephosphorylation of the peptidoglycan carrier lipid; neomycin binds to 30S ribosomal subunit causing misreading of m RNA; polymyxin B disrupts bacterial cell membrane permeability via interaction with phospholipids; hydrocortisone acetate suppresses inflammation by inhibiting phospholipase A2, reducing prostaglandin and leukotriene synthesis.
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)
Treatment of superficial ocular infections caused by susceptible organisms,Reduction of inflammation in corticosteroid-responsive ocular conditions,Off-label: treatment of otitis externa (otic preparations)
Apply topically to affected area 2-5 times daily.
Apply a thin layer to the affected area 3-4 times daily. Ophthalmic: Instill 1-2 drops into the affected eye(s) every 3-4 hours, or more frequently if needed. Otic: Instill 4 drops into the affected ear(s) 3-4 times daily.
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).
Bacitracin: 1.5 h (systemic) but clinically irrelevant as topical. Neomycin: 2-3 h (systemic). Polymyxin B: 4.5-6 h (systemic). Hydrocortisone acetate: 1.5-2.5 h (plasma); clinical effect outlasts serum half-life due to intracellular activity.
Not extensively metabolized. Systemic absorption from topical application is minimal; absorbed drug may undergo hepatic metabolism or be excreted renally unchanged.
Bacitracin: not metabolized, excreted renally; neomycin: minimally metabolized, excreted renally; polymyxin B: metabolism unknown, excreted renally; hydrocortisone acetate: hepatic metabolism via CYP3A4, glucuronidation, sulfation.
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.
Bacitracin: renal (minimal systemic absorption; eliminated unchanged in urine if absorbed). Neomycin: renal (90-95% excreted unchanged in urine after systemic absorption). Polymyxin B: renal (60% excreted unchanged over 24h; prolonged elimination in renal impairment). Hydrocortisone acetate: hepatic metabolism (glucuronidation, sulfation) and renal excretion of metabolites.
Bacitracin: <10% bound to plasma proteins; Neomycin: 0-30% bound; Polymyxin B: 50-70% bound, primarily to alpha-1-acid glycoprotein and lipoproteins.
Bacitracin: ~10% (albumin). Neomycin: <30% (albumin). Polymyxin B: 55-60% (albumin, alpha-1-acid glycoprotein). Hydrocortisone acetate: 90-95% (corticosteroid-binding globulin, 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).
Bacitracin: 0.3 L/kg (minimal distribution). Neomycin: 0.2-0.4 L/kg (extracellular fluid). Polymyxin B: 0.6-0.8 L/kg (extensively bound to cell membranes). Hydrocortisone acetate: 0.3-0.6 L/kg (total body water).
Oral: negligible (<1%) for all three components; topical: minimal systemic absorption via intact skin (<0.5%); ophthalmic/otic: minimal absorption via mucosal surfaces.
Topical/otic/ophthalmic: negligible systemic absorption (<1% for bacitracin, neomycin, polymyxin B; <5% for hydrocortisone acetate). Oral: not applicable (not administered systemically).
No systemic absorption; no dosage adjustment required.
No systemic absorption anticipated with topical, ophthalmic, or otic use; however, for extensive topical application, caution in renal impairment due to neomycin and polymyxin B. GFR <30 m L/min: monitor for nephrotoxicity; reduce frequency if topical use over large areas.
No systemic absorption; no dosage adjustment required.
No specific adjustment required for topical, ophthalmic, or otic use. Hydrocortisone acetate is hepatically metabolized; however, systemic exposure is minimal. Child-Pugh Class C: use with caution if applied to large areas or broken skin.
Apply topically to affected area 2-5 times daily; same as adult dose.
Children: Apply a thin layer to affected area 3-4 times daily. Ophthalmic: Use same as adult dose. Otic: Infants and children: 3 drops into affected ear(s) 3-4 times daily. Safety and efficacy in neonates not established.
Apply topically to affected area 2-5 times daily; same as adult dose.
No specific dose adjustment required. Use with caution in elderly with impaired renal or hepatic function, especially if applied to large areas. Monitor for skin atrophy and systemic effects of hydrocortisone with prolonged use.
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.
None.
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.
Prolonged use may lead to secondary infections (e.g., fungal) or hypersensitivity; ophthalmic use may cause increased intraocular pressure, cataract formation, and delayed wound healing; avoid use in patients with epithelial herpes simplex keratitis; systemic absorption may cause nephrotoxicity and ototoxicity (especially neomycin); use with caution in hepatic impairment.
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.
Hypersensitivity to any component; ocular tuberculosis, viral infections of the cornea (e.g., herpes simplex keratitis), fungal diseases of the eye; untreated purulent infections; use in ears with tympanic membrane perforation (otic preparations).
No significant food interactions; topical application minimizes systemic absorption. No dietary restrictions.
No significant food interactions. No dietary restrictions required.
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.
Teratogenic risk is minimal due to negligible systemic absorption from topical application. No studies report fetal harm from bacitracin, neomycin, polymyxin B, or hydrocortisone acetate when used topically. Avoid prolonged use of high-dose hydrocortisone during first trimester due to potential corticosteroid effects.
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.
Systemic absorption is minimal; topical application likely poses low risk to nursing infant. M/P ratio not established for the combination. Avoid application to breast area to prevent infant ingestion.
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.
No dose adjustment required for topical application during pregnancy. Use sparingly on limited areas to minimize systemic absorption.
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).
This combination product is used for otitis externa and certain ophthalmic infections. The hydrocortisone reduces inflammation, but can mask signs of fungal or viral superinfection. Avoid use in patients with tympanic membrane perforation due to risk of ototoxicity from neomycin and polymyxin B. Neomycin carries sensitization risk; prolonged use may cause contact dermatitis. Monitor for overgrowth of non-susceptible organisms when used beyond 10 days.
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).
Use exactly as prescribed; do not exceed recommended duration.,Avoid contact with eyes unless specifically directed for ophthalmic use.,Do not use if you have a perforated eardrum or ear discharge.,Stop use and notify your doctor if symptoms worsen or persist after 10 days.,Inform your doctor if you experience new pain, redness, or swelling.,Keep this medication out of reach of children.
"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."
"Hydrocortisone, a corticosteroid, may inhibit the hepatic metabolism of doxycycline, a tetracycline antibiotic, leading to increased doxycycline plasma concentrations. This elevation can potentiate doxycycline's adverse effects, such as gastrointestinal disturbance, photosensitivity, and hepatotoxicity. Clinically, this interaction may reduce the therapeutic window of doxycycline, requiring dose adjustment or alternative therapy selection."
"Fluconazole, a potent inhibitor of cytochrome P450 3A4 (CYP3A4), can significantly reduce the hepatic clearance of hydrocortisone, a corticosteroid metabolized primarily by CYP3A4. This interaction leads to increased systemic exposure to hydrocortisone, potentially resulting in exaggerated corticosteroid effects such as hyperglycemia, immunosuppression, and adrenal suppression. Clinically, patients may experience symptoms of Cushing's syndrome or require dose adjustments to avoid toxicity."
"Rifaximin, a non-systemic antibiotic primarily acting in the gastrointestinal tract, may inhibit intestinal P-glycoprotein (P-gp), reducing the efflux of corticosteroids like hydrocortisone. This can lead to increased systemic absorption and elevated serum concentrations of hydrocortisone, potentially enhancing both therapeutic and adverse effects such as hyperglycemia, immunosuppression, and adrenal suppression."
Explore head-to-head clinical comparisons of other medications in the same therapeutic classes.
Common clinical questions about BACITRACIN-NEOMYCIN-POLYMYXIN vs BACITRACIN-NEOMYCIN-POLYMYXIN W/ HYDROCORTISONE ACETATE, 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.. BACITRACIN-NEOMYCIN-POLYMYXIN W/ HYDROCORTISONE ACETATE is a Aminoglycoside Antibiotic that works by Bacitracin inhibits bacterial cell wall synthesis by interfering with dephosphorylation of the peptidoglycan carrier lipid; neomycin binds to 30S ribosomal subunit causing misreading of m RNA; polymyxin B disrupts bacterial cell membrane permeability via interaction with phospholipids; hydrocortisone acetate suppresses inflammation by inhibiting phospholipase A2, reducing prostaglandin and leukotriene synthesis.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between BACITRACIN-NEOMYCIN-POLYMYXIN and BACITRACIN-NEOMYCIN-POLYMYXIN W/ HYDROCORTISONE ACETATE depend on the specific clinical indication. These are both Aminoglycoside Antibiotic agents 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 BACITRACIN-NEOMYCIN-POLYMYXIN W/ HYDROCORTISONE ACETATE is: Apply a thin layer to the affected area 3-4 times daily. Ophthalmic: Instill 1-2 drops into the affected eye(s) every 3-4 hours, or more frequently if needed. Otic: Instill 4 drops into the affected ear(s) 3-4 times daily.. Dosing should always be individualized based on indication, renal and hepatic function, age, and other patient factors.
A moderate-severity drug interaction has been identified when combining BACITRACIN-NEOMYCIN-POLYMYXIN and BACITRACIN-NEOMYCIN-POLYMYXIN W/ HYDROCORTISONE ACETATE. The therapeutic efficacy of Picosulfuric acid can be decreased when used in combination with Bacitracin. Consult your prescriber before combining these medications.
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. BACITRACIN-NEOMYCIN-POLYMYXIN W/ HYDROCORTISONE ACETATE is classified as Category A/B. Teratogenic risk is minimal due to negligible systemic absorption from topical application. No studies report fetal harm from bacitracin, neomycin, polymyxin B, or hydrocortisone a. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.