Both are minimally absorbed oral antibiotics with broad-spectrum coverage for gram-positive and gram-negative aerobes and anaerobes. They can reduce or eliminate ammonia-producing bacteria as well as blood and brain ammonia levels.
NOTE: long term Neomycin use can lead to renal, auditory, and neurological toxicities, as well as antibiotic-induced microfloral resistances.
*Hence Rifaximin is the agent of choice for long term use. Far fewer complications, with a very low risk of inducing bacterial resistance.
References
- Bass NM, Mullen KD, Sanyal A, et al. Rifaximin Treatment in Hepatic Encephalopathy. N Engl J Med. 2010;362:1071-1081