Proper Use of Emetics in Dogs and Cats
Emetics can play a key role in the prevention of clinical signs in dogs and cats who have had oral exposures to toxins. These tips will help you know what emetics may work best for you. (And be sure to read this companion article on when NOT to induce emesis!)
Dogs
Typically, apomorphine and hydrogen peroxide are the emetics of choice with dogs. Published data shows that about 94% of dogs vomit after apomorphine administration and about 90% of dogs vomit after hydrogen peroxide administration. The percentage of the toxin recovered and time to onset of emesis were very similar with both emetics.
Ropinirole ophthalmic is a newer emetic with more limited publications.
APOMORPHINE
Pros: Pet does not need to be exercised; easy to administer.
Cons: Has to be done at a vet hospital and if the owner is far away the delay can be too long for emesis to be effective; can significantly worsen CNS depression, if the agent is likely to cause those signs. (Note: Naloxone will reverse the depressive effects of the apomorphine without reversing the emetic effects, so it can be safely given if depression is seen.)
ROPINIROLE (CLEVORTM)
- Pros: Easy to administer. Less likely to add to CNS depressant effects.
- Cons: Should not be used with pets with underlying ocular disease.
Hydrogen Peroxide
- Pros: Can have owners do at home quickly; readily available (not likely to be back-ordered).
- Cons: Can cause gastritis; can potentially cause GI ulceration or air embolus, if overdosed; pet needs to be walked for the peroxide to have maximum effectiveness.
Cats
XYLAZINE
Generally see vomiting within five minutes that tends not to be prolonged. Xylazine can cause CNS or respiratory depression, but this can be reversed with Antisedan.
DEXMEDETOMIDINE
Like xylazine, emesis with dexmedetomidine tends to occur within quickly and is not prolonged. It may be more effective than xylazine. CNS or respiratory depression are still a concern but they can be reversed with atipamizole (AntisedanTM) or yohimbine.
MIDAZOLAM/HYDROMORPHONE
A combination of midazolam and hydromorphone may be good choice, particularly in feline patients who are elderly or having underlying cardiovascular disease. Not only are they easier on the cardiovascular system than xylazine and dexmedetomadine, they are both reversible if needed.
APOMORPHINE
Typically not recommended as it is not likely to be effective, due to species differences between dogs and cats. The dog's chemoreceptor trigger zone (CRTZ) is controlled largely by dopamine receptors, so apomorphine typically induces emesis. However, the CRTZ in the cat has alpha 2 receptors, so xylazine or dexmedetomadine typically produces a better response.
HYDROGEN PEROXIDE
Like apomorphine, hydrogen peroxide is generally not advised in feline patients because it is not highly effective at making them vomit in a timely manner and cats are more prone to develop gastritis or even hemorrhagic gastritis from hydrogen peroxide than dogs are.
We have lots more on this subject: