Orally administered dexmedetomidine induces emesis in cats

25 June 2024

Induction of emesis in cats is generally challenging and more difficult than in dogs, with success rates reported to be between 43-75%¹. It’s commonly indicated for cats that have ingested toxic substances or foreign materials that may potentially be life-threatening or cause significant morbidity.

A new case series, published in the Journal of Feline Medicine and Surgery, tested a novel route of administration of dexmedetomidine to induce emesis in a small group of cats¹.

Emetic agents typically used in cats include oral hydrogen peroxide, xylazine hydrochloride administered intravenously (IV) or intramuscularly (IM), dexmedetomidine hydrochloride administered IM or IV, and hydromorphone administered subcutaneously. It has been hypothesised that oral administration of alpha2 (α2)-agonists in cats may induce emesis more reliably than if administered IV or IM.

In the new study, six male domestic shorthair cats were given 20 µg/kg dexmedetomidine orally, via syringe positioned over the back of the tongue, and with no efforts (such as holding the mouth shut) to encourage swallowing. The dose was given after known or suspected toxin ingestion of either lily petals, acetaminophen (paracetamol), acetylsalicylic acid (aspirin) or onions.

Emesis was successfully induced in five out of six cats, with only one episode of emesis in all five cats. Time from administration to vomiting was recorded in three cats, with times of 12, 20 and 20 minutes. Time from ingestion of toxin to presentation was between 0.5–3 hours, with a median of 1 hour. The cat that did not vomit after dexmedetomidine was given hydromorphone subcutaneously after reversal of dexmedetomidine, but this did not induce emesis either. Four of the five cats in which emesis was successful had no reported clinical signs consistent with toxin ingestion.

Administering dexmedetomidine orally may be easier than an intramuscular injection, particularly if cats are stressed; can be administered with only minimal restraint of the cat; and the sedative effects of α2-agonists could contribute to reducing stress and allow additional diagnostics or interventions such as IV catheter placement.

This study was limited by a small sample size, and randomised controlled studies are needed to compare the efficacy of orally administered dexmedetomidine with other emetic agents and routes, as well as to determine the ideal doses.

Take home message

Orally administered dexmedetomidine at 20 µg/kg reliably induced emesis in a small group of cats and can be an effective and safe method in cats with no known cardiovascular comorbidities.

Read the full paper:

¹Maxwell KM, Odunayo A & Wissel C (2024) Use of orally administered dexmedetomidine to induce emesis in cats. Journal of Feline Medicine and Surgery. https://doi.org/10.1177/1098612X241248980