Positives

• One patient reported that neomycin twice daily for 28 days finally cleared their SIBO after 2.5 years and they would do it again given the prior quality of life, per a Mayo Clinic Connect SIBO discussion.
  
  
• For methane-positive patients, 87% on the rifaximin plus neomycin combination eradicated methane, versus 33% on neomycin alone, per a PubMed methane SIBO trial.
  
  

Negatives

• Patients commonly describe cramping, nausea, and loose stools that hit harder than rifaximin, with some experiencing tinnitus that prompts discontinuation, per SIBOinfo's antibiotics overview.
  
  
• Clinicians generally limit patients to no more than two rounds of neomycin because of the strong side effect profile, per Mindful Family Medicine's SIBO treatment review.
  
  

Hurdles & Side Effects

• Even though oral neomycin is largely unabsorbed, patients with kidney impairment or pre-existing hearing loss face real ototoxicity and nephrotoxicity warnings that complicate prescribing, per a Mayo Clinic Connect discussion on neomycin toxicity.
  
  
• Most insurers will not cover neomycin for SIBO without a prior authorization documenting positive methane breath testing, per a SIBO antibiotics treatment guide.