Ondansetron

Ondansetron is an antiemetic drug used in animals and humans. It is a serotonin antagonist.

Group

Ondansetron is grouped with antiemetics. In this class of drugs, they inhibit vomiting by various pathways. Other drugs in this group are Trimethobenzamide, Aprepitant, Dolasetron mesylate, Dronabinol, Granisetron, Maropitant, Meclizine, and Mirtazapine.

Mechanism of Action

Ondansetron acts by inhibition of the 5-HT₃ receptor (Serotonin type-3).

Dose Rates

Dog and Cats: 0.1 – 1 mg/kg PO, IM, SC, IV q12-24hr

Indications

• Nausea
• Effective antiemetic in Chemotherapy
• Vomiting in Gastro-Intestinal injury in Parvo viral enteritis

Contraindications

• Intestinal obstruction
• Constipation

Interactions

• In dogs, oral absorption is poor and may be ineffective. Other routes of drug administration work fine.

Adverse effects

• No adverse effects were reported in animals.

Toxicity

Ondansetron overdose has no particular antidote. Patients need to have the proper supportive therapy in order to manage the toxicity.

Preparations

Injectables: 2mg/mL

Tablets: 4mg, 8mg

Syrup: 2mg/5mL