Replying to Ursula Lanigan 27/08/2022 - 10:54
Hey.
Great questions. I am not sue we know exactly which antibiotic is best. I would try and use an antibiotic with as narrow as spectrum as possible. To be honest amox/clav or metronidazole would be fine. I would try and give these antibiotics orally if possible in these cases. I would only use IV if they had significantly altered conciousness.
There are some other options. The goal of oral antibiotic treatments is to reduce the mass of ammonia-producing bacteria in the colon. Neomycin, an aminoglycoside antibiotic, alters the composition of the bacterial flora in the colon, thus decreasing the number of ammonia-producing bacteria. Neomycin (20 mg/kg PO q12h) should be considered in patients intolerant of lactulose. Neomycin can also be administered via a retention enema (15 mg/kg diluted in water q6h after cleansing enema). Neomycin, although poorly absorbed from the intestines when given orally, is highly nephrotoxic and should never be given parenterally.
Studies on the use of oral metronidazole in treatment of HE are limited in human medicine and lacking in veterinary medicine. Metronidazole undergoes extensive hepatic metabolism; therefore, the dose must be reduced in patients with HE (7.5 mg/kg PO q8-12h) to avoid toxic effects. Advantages of using metronidazole over lactulose or neomycin include decreased risk of diarrhea and nephrotoxicity. Maintenance therapy at high doses has been associated with a central vestibular syndrome characterized by ataxia and nystagmus.
I hope that helps.
Scott 🙂
