There are many therapeutic options available for treating or preventing vomiting in cats.

Metoclopramide is a prokinetic that probably lacks central antiemetic action in cats. Its antiemetic action in this species is probably due to the prokinetic effect of increased gastric emptying. Use in cats with intestinal obstruction is contraindicated. The empirical dose in cats is 0.2 to
0.4 mg/kg SC or PO Q 6 H.

Ondansetron and dolasetron are antiemetics that appear to be useful for refractory vomiting. The empirical dosages in cats are 0.5 mg/kg Q 12 H for ondansetron and 0.6 to 1.0 mg/kg IV or PO Q 24 H for dolasetron.

Prochlorperazine and chlorpromazine inhibit vomiting at the chemoreceptor trigger zone and directly at the emetic center. The empirical dosage for both drugs in cats is 0.1 to 0.5 mg/kg SC Q 8 H. These drugs can cause sedation and hypotension. Adjunctive fluid support is strongly recommended.

Maropitant is a neurokinin-1 receptor antagonist. The dosage estimate in cats is 1 mg/kg IV, SC, or PO Q 24 H. Side effects remain to be clearly defined. Pain at the injection site has been reported anecdotally.

Famotidine is a histamine-2 blocker and is not an antiemetic. It may be useful in cases with secondary reflux and esophagitis. The empirical dosage of famotidine in cats is 0.5 to 1 mg/kg Q 24 H or Q 12 H.

Ranitidine is a histamine-2 blocker that may be useful for esophageal reflux or esophagitis and may be preferable to famotidine in cats with both suspected hyperacidity or reflux and gastric atony or megacolon.

The recommended dosage is 2.5 mg/kg IV Q 12 H or 3.5 mg/kg PO Q 12 H.

Omeprazole is a proton-pump inhibitor that is not an antiemetic but is useful for gastroduodenal ulceration or erosive esophagitis. The empirical dosage in cats is 0.5 to 1 mg/kg PO Q 24 H. The safety of long-term omeprazole administration has not been established in cats.

Sucralfate adheres to gastric epithelium and also binds pepsin and bile salts. The empirical dosage of sucralfate is one quarter of a 1-g tablet per cat, Q 8 H or Q 6 H. Aluminum in sucralfate will bind to other drugs and impair absorption.

Cisapride is a prokinetic that increases lower esophageal sphincter pressure, gastric emptying, and small intestinal motility. The recommended dosage of cisapride is 1.5 mg/kg PO Q 12 H. Use is contraindicated for cats with intestinal obstruction.

Commentary: This article reviews the mechanisms of action of agents used to treat or prevent vomiting in cats. Some of the drugs we commonly use are, in fact, poor antiemetics (eg, metoclopramide) in this species and probably lack a central antiemetic effect. The author clarifies whether the effect is truly antiemetic by its effect on the central nervous system chemoreceptor trigger zone and central vomiting center or enteric plexus or whether it acts on the gastrointestinal tract by enhancing motility or reducing/alleviating gastric hyperacidity. She recommends that we base our therapeutic choice on the restrictions imposed by the underlying condition, the cause of emesis, and the mode of action of available treatments.

Acute vomiting in cats: Rational treatment selection. Trepanier L. J FELINE MED SURG 12:225-230, 2010.