Nausea and Vomiting
The pressure from ascitic fluid may cause gastric compression. The patient may benefit from treatment of ascites alongside a pro-kinetic anti-emetic such as metoclopramide.
Nausea may be secondary to accumulation of toxins and therefore centrally acting anti-emetics, such as haloperidol, may be indicated.
Upper gastro-intestinal bleeding due to portal hypertension may damage enterochromaffin cells, leading to release of the neuro-transmitter serotonin (5HT3) which can cause vomiting. 5HT3 antagonists, such as ondansetron and granisetron, could be tried.
Cyclizine and levomepromazine can also be tried as they are broad-spectrum anti-emetics.
Choices of anti-emetics
Haloperidol, Levomepromazine and Cyclizine
Can be used in normal doses for mild to moderate impairment but can precipitate coma in severe impairment.
Advisable to start with a low dose and titrate slowly in this scenario.
Metoclopramide
Can be used in normal doses in mild to moderate impairment.
However, the half-life can double in severe impairment, so it may be advisable to reduce the daily dose by 50%
Ondansetron
Dose not to exceed 8mg/day in moderate or severe impairment as clearance is significantly impaired.
Granisetron
Can be used in normal doses.