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Neomycin and Polymyxin B

Generic name: neomycin/polymyxin b topical

Brand names: Neosporin G U Irrigant

Dosage Forms

Excipient information presented when available (limited, particularly for generics); consult specific product labeling. [DSC] = Discontinued product

Solution, irrigation:

Neosporin G.U. Irrigant: Neomycin 40 mg and polymyxin sulfate B 200,000 units per 1 mL (1 mL [DSC], 20 mL [DSC])

Generic: Neomycin 40 mg and polymyxin B sulfate 200,000 units per 1 mL (1 mL, 20 mL)

Pharmacology

Mechanism of Action

Neomycin: Interferes with bacterial protein synthesis by binding to 30S ribosomal subunits.

Polymyxin B: Binds to phospholipids, alters permeability, and damages the bacterial cytoplasmic membrane permitting leakage of intracellular constituents.

Pharmacokinetics/Pharmacodynamics

Absorption

Topical: Clinically insignificant amounts of neomycin and polymyxin B are absorbed following irrigation of an intact urinary bladder. Systemic absorption may occur from a denuded bladder.

Use: Labeled Indications

Urinary bladder irrigant: Continuous irrigant or rinse for short-term use (up to 10 days) in the urinary bladder of abacteriuric patients to help prevent bacteriuria and gram-negative rod septicemia associated with the use of indwelling catheters.

Contraindications

Hypersensitivity to neomycin, polymyxin B, or any component of the formulation; history of a serious toxic reaction to an aminoglycoside

Dosage and Administration

Dosing: Adult

Urinary bladder irrigant: Intravesical: Add 1 mL irrigant to 1,000 mL isotonic saline solution per day as a continuous irrigation for up to 10 days.

Dosing: Geriatric

Refer to adult dosing.

Dosing: Pediatric

Urinary bladder irrigant: Limited data available (Elliott 2005); efficacy results variable (Warren 1978); most experience in patients with neurogenic bladder or spinal cord injury: Children and Adolescents: Irrigant solution (neomycin 40 mg/polymyxin B 200,000 units/L): Intravesical: 10 mL instilled at the end of each catheterization and retained until next catheterization (Mulcahy 1979); in older adolescents, 30 mL 2 to 3 times daily has been used for asymptomatic bacteriuria (Linsenmeyer 1999; Waites 2006). Note: Use has generally been replaced with other agents (eg, saline, gentamicin) (Defoor 2006; Dray 2017; van den Heijkant 2011; van Nieuwkoop 2010).

Reconstitution

Concentrated irrigant solution must be diluted prior to administration; add 1 mL of irrigant to 1,000 mL of isotonic saline solution.

Administration

For bladder irrigation only; not for injection. Connect irrigation container to the inflow lumen of a 3-way catheter to permit continuous irrigation of the urinary bladder. Rinsing of the bladder should be continuous; the inflow or rinse solution should not be interrupted for more than a few minutes. Adjust flow rate to 1,000 mL/24 hours; if patient’s urine output exceeds 2,000 mL/day, increase flow rate to 2,000 mL/24 hours.

Storage

Store at 2°C to 8°C (36°F to 46°F). Prepared dilutions should be stored in the refrigerator and discarded after 48 hours.

Drug Interactions

Acarbose: Neomycin may enhance the adverse/toxic effect of Acarbose. Neomycin may decrease the metabolism of Acarbose. Monitor therapy

Amphotericin B: May enhance the nephrotoxic effect of Aminoglycosides. Monitor therapy

Arbekacin: May enhance the nephrotoxic effect of Aminoglycosides. Arbekacin may enhance the ototoxic effect of Aminoglycosides. Monitor therapy

Ataluren: May enhance the adverse/toxic effect of Aminoglycosides. Specifically, an increased risk of nephrotoxicity may occur with the concomitant use of ataluren and aminoglycosides. Avoid combination

Bacitracin (Systemic): Polymyxin B may enhance the nephrotoxic effect of Bacitracin (Systemic). Avoid combination

Bacitracin (Systemic): Neomycin may enhance the nephrotoxic effect of Bacitracin (Systemic). Avoid combination

BCG (Intravesical): Antibiotics may diminish the therapeutic effect of BCG (Intravesical). Avoid combination

BCG Vaccine (Immunization): Antibiotics may diminish the therapeutic effect of BCG Vaccine (Immunization). Monitor therapy

Bisphosphonate Derivatives: Aminoglycosides may enhance the hypocalcemic effect of Bisphosphonate Derivatives. Monitor therapy

Botulinum Toxin-Containing Products: Aminoglycosides may enhance the neuromuscular-blocking effect of Botulinum Toxin-Containing Products. Monitor therapy

Capreomycin: May enhance the neuromuscular-blocking effect of Polymyxin B. Monitor therapy

CARBOplatin: Aminoglycosides may enhance the ototoxic effect of CARBOplatin. Especially with higher doses of carboplatin. Monitor therapy

Cardiac Glycosides: Aminoglycosides may decrease the serum concentration of Cardiac Glycosides. This effect has only been demonstrated with oral aminoglycoside administration. Monitor therapy

Cefazedone: May enhance the nephrotoxic effect of Polymyxin B. Monitor therapy

Cephalosporins (2nd Generation): May enhance the nephrotoxic effect of Aminoglycosides. Monitor therapy

Cephalosporins (3rd Generation): May enhance the nephrotoxic effect of Aminoglycosides. Monitor therapy

Cephalosporins (4th Generation): May enhance the nephrotoxic effect of Aminoglycosides. Monitor therapy

Cephalothin: May enhance the nephrotoxic effect of Aminoglycosides. Monitor therapy

Cephradine: May enhance the nephrotoxic effect of Aminoglycosides. Monitor therapy

Cholera Vaccine: Antibiotics may diminish the therapeutic effect of Cholera Vaccine. Management: Avoid cholera vaccine in patients receiving systemic antibiotics, and within 14 days following the use of oral or parenteral antibiotics. Avoid combination

CISplatin: May enhance the nephrotoxic effect of Aminoglycosides. Monitor therapy

Colistimethate: Aminoglycosides may enhance the nephrotoxic effect of Colistimethate. Aminoglycosides may enhance the neuromuscular-blocking effect of Colistimethate. Consider therapy modification

CycloSPORINE (Systemic): Aminoglycosides may enhance the nephrotoxic effect of CycloSPORINE (Systemic). Monitor therapy

Distigmine: Aminoglycosides may diminish the therapeutic effect of Distigmine. Monitor therapy

Foscarnet: May enhance the nephrotoxic effect of Aminoglycosides. Avoid combination

Lactobacillus and Estriol: Antibiotics may diminish the therapeutic effect of Lactobacillus and Estriol. Monitor therapy

Loop Diuretics: May enhance the adverse/toxic effect of Aminoglycosides. Specifically, nephrotoxicity and ototoxicity. Monitor therapy

Mannitol (Systemic): May enhance the nephrotoxic effect of Aminoglycosides. Avoid combination

Mecamylamine: Polymyxin B may enhance the neuromuscular-blocking effect of Mecamylamine. Avoid combination

Methoxyflurane: May enhance the nephrotoxic effect of Polymyxin B. Avoid combination

Neuromuscular-Blocking Agents: Polymyxin B may enhance the neuromuscular-blocking effect of Neuromuscular-Blocking Agents. Consider therapy modification

Nonsteroidal Anti-Inflammatory Agents: May decrease the excretion of Aminoglycosides. Data only in premature infants. Monitor therapy

Oxatomide: May enhance the ototoxic effect of Aminoglycosides. Monitor therapy

Penicillins: May decrease the serum concentration of Aminoglycosides. Primarily associated with extended spectrum penicillins, and patients with renal dysfunction. Exceptions: Amoxicillin; Ampicillin; Bacampicillin; Cloxacillin; Dicloxacillin; Nafcillin; Oxacillin; Penicillin G (Parenteral/Aqueous); Penicillin G Benzathine; Penicillin G Procaine; Penicillin V Benzathine; Penicillin V Potassium. Consider therapy modification

Regorafenib: Neomycin may decrease serum concentrations of the active metabolite(s) of Regorafenib. Monitor therapy

Sodium Picosulfate: Antibiotics may diminish the therapeutic effect of Sodium Picosulfate. Management: Consider using an alternative product for bowel cleansing prior to a colonoscopy in patients who have recently used or are concurrently using an antibiotic. Consider therapy modification

SORAfenib: Neomycin may decrease the serum concentration of SORAfenib. Monitor therapy

Tenofovir Products: Aminoglycosides may increase the serum concentration of Tenofovir Products. Tenofovir Products may increase the serum concentration of Aminoglycosides. Monitor therapy

Vancomycin: May enhance the nephrotoxic effect of Aminoglycosides. Monitor therapy

Vitamin K Antagonists (eg, warfarin): Neomycin may enhance the anticoagulant effect of Vitamin K Antagonists. Monitor therapy

Adverse Reactions

Frequency not defined.

Central nervous system: Localized burning

Dermatologic: Contact dermatitis, erythema, skin rash, urticaria

Genitourinary: Bladder mucosa irritation, nephrotoxicity

Neuromuscular & skeletal: Neuromuscular blockade

Otic: Ototoxicity

Warnings/Precautions

Concerns related to adverse effects:

  • Superinfection: Prolonged use may result in fungal or bacterial superinfection, including C. difficile-associated diarrhea (CDAD) and pseudomembranous colitis; CDAD has been observed >2 months postantibiotic treatment.
  • Systemic toxicity: Ototoxicity, nephrotoxicity, and neuromuscular blockade may occur if systemically absorbed. Avoid use in patients with defects in the bladder mucosa or bladder wall (eg, vesical rupture) or in association with operative procedure on the bladder wall due to the risk of systemic toxicity; absorption of neomycin from the denuded bladder surface has been reported.

Disease-related concerns:

  • Renal impairment: Use with caution in patients with renal impairment; risk for toxicity is increased.

Concurrent drug therapy issues:

  • Drug-drug interactions: Potentially significant interactions may exist, requiring dose or frequency adjustment, additional monitoring, and/or selection of alternative therapy. Consult drug interactions database for more detailed information.

Special populations:

  • Dehydrated patients: Use with caution; risk for toxicity is increased.
  • Elderly: Use with caution; risk for toxicity is increased.
  • Pediatric: Use with caution in infants; risk for toxicity is increased.

Other warnings/precautions:

  • Appropriate use: Irrigant is for urinary bladder irrigation only. Risk of systemic toxicity is low if irrigation of intact urinary bladder does not exceed 10 days.
  • Prolonged treatment: Patients receiving high doses of prolonged treatment are at increased risk for toxicity.

Monitoring Parameters

Urinalysis, renal function.

Pregnancy

Pregnancy Considerations

Animal reproduction studies have not been conducted with this combination; however, there are reports of total irreversible bilateral congenital deafness in children whose mothers received streptomycin during pregnancy. See individual agents.

Patient Education

  • Discuss specific use of drug and side effects with patient as it relates to treatment. (HCAHPS: During this hospital stay, were you given any medicine that you had not taken before? Before giving you any new medicine, how often did hospital staff tell you what the medicine was for? How often did hospital staff describe possible side effects in a way you could understand?)
  • Patient may experience bladder irritation or skin irritation. Have patient report immediately to prescriber trouble hearing, unable to pass urine, or change in amount of urine passed (HCAHPS).
  • Educate patient about signs of a significant reaction (eg, wheezing; chest tightness; fever; itching; bad cough; blue skin color; seizures; or swelling of face, lips, tongue, or throat). Note: This is not a comprehensive list of all side effects. Patient should consult prescriber for additional questions.

Intended Use and Disclaimer: Should not be printed and given to patients. This information is intended to serve as a concise initial reference for healthcare professionals to use when discussing medications with a patient. You must ultimately rely on your own discretion, experience and judgment in diagnosing, treating and advising patients.

Source: Wolters Kluwer Health. Last updated November 27, 2019.