Neomicina (Neomycin Sulfate)

• Neomycin is used in gastrointestinal applications where bacterial reduction is required.
• Intestinal decontamination before surgery: reduces pathogenic gut flora to lower postoperative infection risk.
• Hepatic encephalopathy: lowers intestinal ammonia‑producing bacteria, helping control neuropsychiatric symptoms.
• Prevention of bacterial overgrowth in the gastrointestinal tract: limits proliferation of harmful microbes in conditions such as small‑intestine bacterial overgrowth.

• Neomycin binds to the bacterial 30S ribosomal subunit, causing misreading of mRNA and inhibition of protein synthesis. This bactericidal action disrupts essential cellular functions, leading to rapid bacterial cell death, particularly against aerobic gram‑negative organisms and some gram‑positive strains within the gastrointestinal lumen. Because it is poorly absorbed from the gut, its activity remains localized, minimizing systemic exposure while providing high concentrations at the site of infection.

Oral neomycin may cause a range of adverse reactions, varying from mild to severe.

Common Side Effects

• Nausea
• Vomiting
• Diarrhea
• Abdominal discomfort
• Skin rash

Serious or Rare Side Effects

• Ototoxicity (hearing loss or balance disturbances)
• Nephrotoxicity (renal impairment)
• Severe allergic reactions such as anaphylaxis or Stevens‑Johnson syndrome

• When prescribing oral neomycin, clinicians should observe several safety considerations.
• Renal function monitoring: assess baseline creatinine and adjust use in renal impairment.
• Auditory monitoring: watch for signs of ototoxicity, especially with prolonged therapy.
• Hypersensitivity caution: discontinue if rash, itching, or swelling develop.
• Gastrointestinal caution: avoid in patients with inflammatory bowel disease or ulcerative colitis due to risk of worsening symptoms.
• Duration limitation: limit treatment length to the minimum necessary to achieve bacterial reduction.
• Store below 25°C: keep in the original packaging, protect from moisture and heat.

Neomycin can interact with other medicines, influencing its safety profile.

Major Interactions (Avoid)

• Concurrent nephrotoxic agents (e.g., amphotericin B, loop diuretics, other aminoglycosides): increased risk of renal toxicity.
• Co‑administration with ototoxic drugs (e.g., vancomycin, loop diuretics): heightened risk of hearing loss.

Moderate Interactions (Monitor Closely)

• NSAIDs: may augment nephrotoxic potential, monitor renal function.
• Muscle relaxants or neuromuscular blockers: may enhance neuromuscular blockade, observe for weakness.
• Antacids containing magnesium or aluminum: may reduce oral absorption, consider timing separation.