Apomorphine, also known as Apokyn®, is a derivative of morphine. Its primary action in dogs and cats is to induce vomiting.
Unlike morphine, apomorphine does not alleviate pain.
Apomorphine stimulates the dopamine receptors in the specific part of the brain that induces vomiting.
This drug is typically only given to dogs. Its use in cats is controversial since morphine type drugs can cause an excitatory reaction in cats.
Apomorphine is one of the most effective medications that can induce vomiting in dogs. As with all vomiting medications, usually only 40 to 60 percent of the stomach's contents are removed.
The drug is slowly absorbed after oral ingestion so it is usually given as an injection or topical on the eye. When given intravenously, vomiting occurs rapidly. After intramuscular injection, vomiting usually occurs within 5 minutes but may be more prolonged.
Topical administration of apomorphine to the conjunctival sac of the eye is usually effective but is less reliable than injectable.
Apomorphine is a prescription drug and can only be obtained from a veterinarian or by prescription from a veterinarian.
This drug is not approved for use in animals by the Food and Drug Administration but it is prescribed legally by veterinarians as an extra-label drug.
Brand Names and Other Names of Apomorphine
This drug is registered for use in humans only.
Human formulations: Apokyn®. Apomorphine is primarily available through compounding pharmacies.
Veterinary formulations: None
Uses of Apomorphine for Dogs and Cats
Apomorphine is used to induce vomiting in dogs.
Precautions and Side Effects
While generally safe and effective when prescribed by a veterinarian, apomorphine can cause side effects in some animals.
Apomorphine should not be used in animals with known hypersensitivity or allergy to the drug.
Apomorphine should be avoided in animals that are having breathing difficulty, seizing, physically weak or comatose.
Vomiting should not be induced if the animal has already vomited several times or has ingested acid, caustic agents or petroleum distillates.
If vomiting does not occur within the expected time, additional doses will likely not result in vomiting and may result in toxicity.
Apomorphine may interact with other medications. Consult with your veterinarian to determine if other drugs your pet is receiving could interact with apomorphine. Such drugs include prochlorperazine, chlorpromazine or certain narcotics.
Apomorphine can cause nervous system depression or stimulation but tends to cause more stimulatory effects.
Protracted vomiting can occur after administration of apomorphine. Excitement, restlessness, nervous system depression or respiratory depression can occur, especially if an overdose is given.
How Apomorphine is Supplied
Apomorphine is typically only available through compounding pharmacies at varying concentrations.
Dosing Information of Apomorphine for Dogs and Cats
Medication should never be administered without first consulting your veterinarian. This medication is almost always given in a hospital setting.
IN dogs, apomorphine is dosed at 0.015 mg per pound (0.03 mg/kg) IV or 0.02 mg per pound (0.04 mg/kg) IM (IV route is preferred).
The use of apomorphine in cats is controversial but can be given at a dose of 0.02 mg per pound (0.04 mg/kg) IV or 0.04 mg per pound (0.08 mg/kg) IM or SQ.
If not injected, a portion of the tablet may be crushed in a syringe and dissolved with few drops of water and administered into the conjunctival sac, approximately 1 tablet per 50 pounds. After sufficient vomiting occurs, rinse the conjunctival sac to remove residual apomorphine.