Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
BACITRACIN-NEOMYCIN-POLYMYXIN vs ACULAR LS
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.
Selective COX-2 inhibitor; inhibits prostaglandin synthesis, reducing ocular inflammation and pain.
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)
FDA: Treatment of postoperative inflammation in patients who have undergone cataract surgery,Off-label: Relief of ocular pain, photophobia, and inflammation associated with corneal abrasion or refractive surgery
Apply topically to affected area 2-5 times daily.
1 drop in the affected eye(s) four 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).
The terminal elimination half-life is approximately 1.8 hours (range 1.2–2.5 hours) following topical ocular administration. This short half-life is consistent with rapid clearance from the systemic circulation.
Not extensively metabolized. Systemic absorption from topical application is minimal; absorbed drug may undergo hepatic metabolism or be excreted renally unchanged.
Primarily hepatic via CYP2C9; undergoes glucuronidation and oxidation to inactive metabolites.
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 excretion of metabolites and unchanged drug accounts for approximately 26% of the dose. Fecal excretion accounts for approximately 74% of the dose, primarily 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.
Ketorolac is highly protein bound, approximately 99% bound to plasma proteins, primarily 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).
The volume of distribution is approximately 0.12 L/kg, indicating distribution primarily into extracellular fluid with limited tissue penetration.
Oral: negligible (<1%) for all three components; topical: minimal systemic absorption via intact skin (<0.5%); ophthalmic/otic: minimal absorption via mucosal surfaces.
Ophthalmic bioavailability is approximately 2% of the administered dose due to extensive nasolacrimal drainage and systemic absorption. Oral bioavailability of ketorolac is approximately 80-100%, but this route is not used for ophthalmic formulations.
No systemic absorption; no dosage adjustment required.
No dosage adjustment required for renal impairment
No systemic absorption; no dosage adjustment required.
No dosage adjustment required for hepatic impairment but use with caution in severe hepatic disease due to potential for increased systemic exposure
Apply topically to affected area 2-5 times daily; same as adult dose.
Safety and efficacy in pediatric patients below 2 years of age have not been established; for children 2 years and older, same as adult dosing
Apply topically to affected area 2-5 times daily; same as adult dose.
No specific dose adjustment recommended; use with caution due to increased incidence of age-related ocular conditions
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.
Increased risk of bleeding and bleeding-related adverse events due to platelet inhibition,May prolong bleeding time,Cross-sensitivity with aspirin and other NSAIDs,Caution in patients with prior history of corneal epithelial defects or ocular surgery,Not for intraocular injection
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 ketorolac tromethamine or any component of the formulation,Patients with active peptic ulcer disease, recent GI bleeding, or perforation,Patients with advanced renal disease or at risk for renal failure,Patients with known history of asthma, urticaria, or allergic-type reactions after taking aspirin or other NSAIDs
No significant food interactions; topical application minimizes systemic absorption. No dietary restrictions.
No known food interactions for ophthalmic ketorolac. However, maintain good hydration and nutrition to support corneal healing.
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.
Ketorolac tromethamine, the active ingredient in ACULAR LS, is a nonsteroidal anti-inflammatory drug (NSAID). In animal reproduction studies, administration of ketorolac during organogenesis resulted in increased embryofetal mortality, delayed ossification, and increased incidence of skeletal abnormalities at doses less than the maximum recommended human ophthalmic dose. However, systemic exposure following ocular administration is very low. NSAIDs are generally avoided during pregnancy, especially in the third trimester, due to the risk of premature closure of the ductus arteriosus and oligohydramnios. The risk is considered low for ophthalmic use but should be used only if clearly needed.
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.
It is not known whether ketorolac is excreted in human milk after ophthalmic administration. Systemic levels are low, and following oral administration, ketorolac is excreted in breast milk at low concentrations (M/P ratio approximately 0.37). Due to the potential for adverse effects on the nursing infant, caution should be exercised. The low systemic absorption likely poses minimal risk.
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 dosing adjustments are necessary for ophthalmic use during pregnancy due to negligible systemic absorption. Standard dosing (1 drop in the affected eye(s) four times daily) is recommended. Systemic NSAIDs may require dose adjustment due to increased volume of distribution and renal changes, but this does not apply to topical ocular ketorolac.
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).
ACULAR LS (ketorolac tromethamine ophthalmic solution 0.4%) is a nonsteroidal anti-inflammatory drug (NSAID) indicated for the reduction of ocular pain and photophobia following corneal refractive surgery. Use with caution in patients with known bleeding tendencies or those on anticoagulants due to increased risk of ocular bleeding. Avoid concurrent use with other NSAIDs or steroids to minimize corneal adverse effects. Monitor for corneal epithelial breakdown or delayed healing.
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).
Do not touch the dropper tip to any surface to avoid contamination.,Remove contact lenses before instillation and wait at least 10 minutes before reinserting.,Use only in the affected eye(s) as prescribed; do not use for longer than directed.,Temporary stinging or burning may occur upon instillation.,Report any persistent pain, redness, or visual changes to your doctor immediately.,Avoid driving or operating machinery if vision is blurred after use.
"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 ACULAR LS, 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.. ACULAR LS is a NSAID Ophthalmic that works by Selective COX-2 inhibitor; inhibits prostaglandin synthesis, reducing ocular inflammation and pain.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between BACITRACIN-NEOMYCIN-POLYMYXIN and ACULAR LS 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 ACULAR LS is: 1 drop in the affected eye(s) four times daily. 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 ACULAR LS 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. ACULAR LS is classified as Category C. Ketorolac tromethamine, the active ingredient in ACULAR LS, is a nonsteroidal anti-inflammatory drug (NSAID). In animal reproduction studies, administration of ketorolac during org. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.