What is the oral (po) dosage of Neomycin (an amino glycoside) for adults?

Oral Neomycin Dosage for Adults

For adults requiring oral neomycin, the standard dosage is 4 to 12 grams per day divided into multiple doses, with treatment duration not exceeding two weeks due to toxicity risk. 1

Indications and Dosing

Hepatic Encephalopathy/Hepatic Coma

• 4 to 12 grams of neomycin sulfate per day divided into multiple doses for 5-6 days 1
• For chronic hepatic insufficiency, doses up to 4 grams daily may be necessary if less toxic alternatives aren't available 1
• Treatment periods longer than two weeks are not recommended due to increased risk of toxicity 1

Preoperative Bowel Preparation

• 1 gram of neomycin sulfate orally at 1:00 PM, 2:00 PM, and 11:00 PM on the day before surgery, typically combined with 1 gram of erythromycin base at the same intervals 1, 2
• This regimen has shown superior infection prevention compared to some systemic antibiotic prophylaxis approaches 2

Important Considerations

Limited Absorption and Use

• Aminoglycosides, including neomycin, are poorly absorbed from the gastrointestinal tract 3
• Oral neomycin is primarily limited to:
  • Bowel preparation before colorectal surgery 1, 2
  • Management of hepatic encephalopathy 1, 3
  • Intestinal decontamination in specific clinical scenarios 4

Safety Concerns

• To minimize toxicity risk, use the lowest possible dose and shortest treatment duration 1
• Monitor for potential adverse effects:
  • Nephrotoxicity and ototoxicity may occur with prolonged use or accumulation 1
  • Gastrointestinal effects including nausea, vomiting, and risk of C. difficile colitis 5
  • Rare cases of systemic contact dermatitis have been reported 5

Monitoring

• For patients requiring extended therapy, frequent monitoring for drug toxicity is mandatory 1
• Neomycin serum concentrations should be monitored to avoid potentially toxic levels in prolonged use 1
• Risk of developing neomycin-induced toxicity increases progressively when treatment must be extended 1

Special Populations

Patients with Renal Impairment

• Use with extreme caution in patients with renal dysfunction 1
• Consider dose adjustment or alternative agents in patients with impaired renal function 6

Resistance Considerations

• While resistance to aminoglycosides has historically been rare, it is increasing in frequency 7
• Avoiding prolonged use helps decrease the risk of developing resistance 7, 8