Induce emesis in animals that have been recently exposed (< 30 minutes) and are exhibiting no clinical signs. In cats, give
xylazine (0.44 mg/kg intramuscularly) to induce emesis,7 and in dogs, give apomorphine (0.03 mg/kg intravenously; 0.04 mg/kg intramuscularly).7 If apomorphine is only available in tablet form, it may be administered into the conjunctival sac. When using the ocular
method, a quarter of a 6-mg tablet (in any sized dog) should be crushed, diluted with a few drops of saline solution, and
administered into the conjunctival sac. After emesis has occurred, gently rinse the conjunctival sac with saline solution
to reduce the risk for ocular irritation.
Alternatively in dogs, 3% active hydrogen peroxide can be orally administered at a dose of 1 to 2 ml/kg (generally not exceeding
45 ml as a total dose). This dose may be repeated just once since multiple doses of hydrogen peroxide may result in gastritis.8 Hydrogen peroxide is generally not recommended for cats because of their increased risk for gastritis.9
For dose exposures > 2 mg/kg in dogs and cats, a single dose of activated charcoal with a cathartic can be administered to
hinder absorption (1 g/kg of activated charcoal diluted in water to achieve a 1 g/10 ml concentration or 10 ml/kg of a 10%
activated charcoal suspension) may be warranted.7 Collect baseline electrolyte values at presentation, and monitor them for four hours after activated charcoal administration
to assess for changes to the patient's sodium concentration.
Closely monitor heart rate and blood pressure in exposed patients. Baseline electrolyte values should be obtained and monitored
for changes as marked gastrointestinal effects develop or hydration becomes a concern. In cases in which activated charcoal
has been administered, monitor electrolyte values for at least four hours (see "Decontamination" above).
Marked tremor activity may result in hyperthermia and rhabdomyolysis with subsequent hyperkalemia and renal damage; thus,
in patients exhibiting serious clinical signs, also monitor renal indices.
Monitor patients that are asymptomatic after ingestion for six hours before their release.
TREATMENT OF TOXICOSIS
If a patient has developed agitation or hyperactivity and is normotensive or hypertensive, acepromazine at a dosage of 0.02
mg/kg intravenously or intramuscularly may be administered for sedation. Tremors may be controlled with methocarbamol (50
to 220 mg/kg intravenously slowly to effect, not to exceed 330 mg/kg/day). Seizure activity can be treated with diazepam (0.5
to 2 mg/kg intravenously in dogs, 0.25 to 1 mg/kg intravenously in cats starting at lower doses and given to effect), but
administer this drug with caution; occasionally patients may develop paradoxical excitation after administration. Alternatively,
a barbiturate such as phenobarbital (2 to 5 mg/kg intravenously to effect, may be repeated at 20-minute intervals up to two
times), gas anesthesia, or propofol (5 to 6 mg/kg intravenously) may be given to control seizures.7
Tachycardia and hypertension may resolve after sedation. If tachycardia persists and the patient is normotensive, propranolol
(0.02 to 0.06 mg/kg intravenously slowly to effect), a nonselective beta-adrenergic antagonist, may be administered to obtain
the desired heart rate.7 A nitroprusside continuous-rate infusion may be given to manage hypertension (> 200 mm Hg systolic arterial blood pressure).
Administer an initial a dose of 1 or 2 µg/kg/min in dogs (0.5 µg/kg/min in cats), and then increase the dose incrementally
every three to five minutes until the target blood pressure is attained. The blood pressure should be reduced by 25% over
four hours to allow the cerebral vessels to readapt.7
If tremor activity occurs, fluid therapy (balanced, isotonic crystalloid) is indicated to aid in thermoregulation and provide
renal support. Fluids should be administered intravenously starting at the maintenance rate of 45 to 60 ml/kg/day, adjusting
for ongoing needs and blood pressure and hydration changes. If fluids are administered, the patient should be monitored closely
for hypertension and potential fluid overload.