nee-oh-MYE-sin

Therapeutic Classification: anti-infectives

Pharmacologic Classification: aminoglycosides

• Preparation of the GI tract for surgery.
• Treatment of diarrhea caused by Escherichia coli.
• To decrease the number of ammonia-producing bacteria in the gut as part of the management of hepatic encephalopathy.

• Inhibits protein synthesis in bacteria at level of 30S ribosome.

• Bactericidal action.

Spectrum:

• Notable for activity against:
  • Klebsiella pneumoniae,
  • Escherichia coli,
  • Proteus,
  • Serratia,
  • Acinetobacter,
  • Staphylococcus aureus.

Absorption: Minimal systemic absorption, but may accumulate in patients with renal failure.

Distribution: Widely distributed throughout extracellular fluid; crosses the placenta; small amounts enter breast milk. Poor penetration into CSF.

Metabolism/Excretion: Excretion is >90% renal.

Half-life: 2–4 hr (increased in renal impairment).

(blood levels)

Contraindicated in:

• Hypersensitivity to neomycin or other aminoglycosides
• Intestinal obstruction.

Use Cautiously in:

• Renal impairment (lower doses are recommended)
• Hearing impairment
• Geri: Geriatric patients
• Neuromuscular diseases such as myasthenia gravis
• OB: Lactation: Safety not established
• Pedi: Safety not established.

GI: diarrhea, nausea, vomiting.
Misc: hypersensitivity reactions.

Interactions are listed for systemically absorbed drug

Drug-Drug:

• May enhance possible respiratory paralysis after inhalation anesthetics or neuromuscular blockers.
• ↑incidence of ototoxicity with loop diuretics.
• ↑incidence of nephrotoxicity with other nephrotoxic drugs.
• May ↑anticoagulant effects of warfarin.
• May ↓absorption of digoxin and methotrexate.

Preoperative Intestinal Antisepsis

• PO (Adults): 1 g every hr for 4 doses, then 1 g every 4 hr for 5 doses or 1 g at 1 PM, 2 PM, and 11 PM on day before surgery.
• PO (Children): 15 mg/kg every 4 hr for 2 days or 25 mg/kg at 1 PM, 2 PM, and 11 PM on day before surgery.

Hepatic Encephalopathy

• PO (Adults): 1–3 g every 6 hr for 5–6 days; may be followed by 4 g/day chronically.
• PO (Children): 12.5–25 mg/kg every 6 hr for 5–6 days (max dose 12 g/day).

(Generic available)

• Tablets: 500 mg;
• In combination with: other topical antibiotics or anti-inflammatory agents for skin, ear, and eye infections. See Appendix [not included in this PDA edition].

• Assess patient for infection (vital signs, wound appearance, sputum, urine, stool, WBC) at beginning of and throughout therapy.
• Hepatic Encephalopathy: Monitor neurologic status. Prior to administering oral medication, assess patient's ability to swallow.

• Keep patient well hydrated (1500–2000 mL/day) during therapy.
• Preoperative Bowel Prep: Neomycin is usually used in conjunction with erythromycin, a low-residue diet, and a cathartic or enema.
• PO: May be administered without regard to meals.

• Advise patient of the importance of drinking plenty of liquids.
• PO: Instruct patient to take as directed for full course of therapy. Missed doses should be taken as soon as possible if not almost time for next dose; do not double doses.
  • Caution patient that medication may cause nausea, vomiting, or diarrhea.

• Resolution of the signs and symptoms of infection. If no response is seen within 3–5 days, new cultures should be taken.
• Prevention of infection in intestinal surgery.
• Improved neurologic status in hepatic encephalopathy.