Apomorphine
Apomorphine hydrochloride
Also known as: Apokyn · APO-go · Apofin · Apokinon · Apomine · Britaject · Ixense · Taluvian · Uprima · Apometic · apomorphini hydrochloridum
Reviewed by the VetSheet Veterinary TeamUpdated Apr 5, 2026Evidence-based veterinary reference
Doses are a clinical reference for licensed veterinary professionals. Always confirm against the current label and the individual patient.
Dosing by species
🌎 NA — North America🌍 EU — Europe
Dogs
| Indication | Dose | Route | Frequency | Duration | Region |
|---|---|---|---|---|---|
| Induction of emesis | 0.03 mg/kg IV or 0.04 mg/kg IM (IV route preferred); alternatively a portion of tablet may be crushed in a syringe, dissolved with few drops of water and administered into the conjunctival sac. After sufficient vomiting occurs, rinse conjunctival sac free of unabsorbed apomorphine. | IV/IM/Topical | Once | — | 🌎 NA |
| Induction of emesis | 0.04 mg/kg IV or 0.08 mg/kg IM or SC | IV/IM/SC | Once | — | 🌎 NA |
| Induction of emesis | 0.04 mg/kg IV, 0.07 mg/kg IM, or 0.25 mg/kg into the conjunctival sac | IV/IM/Topical | Once | — | 🌎 NA |
| Induction of emesis | 0.2 mg/kg | SC | single dose | single dose | 🌍 EU |
| Induction of emesis | 20-40 μg/kg | IV | single dose | single dose | 🌍 EU |
- Induction of emesis: IV route preferred.
- Induction of emesis: Authorized dose. Do not repeat if ineffective.
- Induction of emesis: Non-authorized dose and route but some evidence suggests it is at least as effective.
Cats
| Indication | Dose | Route | Frequency | Duration | Region |
|---|---|---|---|---|---|
| Induction of emesis | 0.04 mg/kg IV or 0.08 mg/kg IM or SC | IV/IM/SC | Once | — | 🌎 NA |
| Induction of emesis | Not recommended | IM | single dose | single dose | 🌍 EU |
- Induction of emesis: Use of apomorphine in cats is controversial and many recommend not using in this species.
- Induction of emesis: Xylazine is a potent emetic in cats and at least as safe.
Doses are a clinical reference for licensed veterinary professionals. Always confirm against the current label and the individual patient.
Overview
Apomorphine is a synthetic opiate derivative, but unlike morphine, it lacks significant analgesic properties. It is widely considered the emetic of choice for dogs in veterinary medicine for the prompt removal of ingested toxins.
- Rapid Action: Produces emesis very rapidly when administered parenterally (IV/IM) or topically to the conjunctival sac.
- Species Specificity: Highly effective in dogs. Its use in cats is controversial and generally not recommended due to lower efficacy and potential safety concerns.
- Limitations: Like all emetics, it generally only removes 40-60% (maximum 80%) of stomach contents. Successful induction of emesis does not eliminate the need for further toxicological monitoring or therapy (e.g., activated charcoal).
Mechanism of action
Apomorphine acts as a non-selective dopamine agonist.
It directly stimulates D2-dopaminergic receptors in the chemoreceptor trigger zone (CRTZ) located in the area postrema of the medulla oblongata.
Mechanism Pathway: Apomorphine administration → Crosses the blood-brain barrier → Stimulates D2 receptors in the CRTZ → Activates the central vomiting center → Initiates the emetic reflex.
Clinical Pearl: The CRTZ in dogs is highly sensitive to dopamine, making apomorphine highly effective. In contrast, the feline CRTZ is mediated primarily by alpha-2 adrenergic receptors, which is why alpha-2 agonists (like xylazine or dexmedetomidine) are the preferred emetics for cats, while apomorphine is often ineffective.
Safety & warnings
Contraindications
- Rodents and rabbits (unable to vomit or lack stomach wall strength)
- Hypoxia, dyspnea, or shock
- Lack of normal pharyngeal reflexes (risk of aspiration)
- Seizuring, comatose, or severely CNS-depressed patients
- Patients who have already vomited repeatedly
- Ingestion of strong acids, alkalis, or other caustic agents (risk of esophageal/gastric rupture)
- Ingestion of petroleum distillates (unless toxicity risk outweighs aspiration risk)
- Ingestion of strychnine or other CNS stimulants (may precipitate seizures)
- Oral opiate or other CNS depressant (e.g., barbiturates) toxicity
- Hypersensitivity to morphine
Adverse effects
- Protracted vomiting
- CNS depression (lethargy, sedation)
- CNS stimulation (excitement, restlessness)
- Respiratory depression
- Corneal ulcers (anecdotal, associated with conjunctival administration)
Precautions
If vomiting does not occur within the expected time after apomorphine administration, repeated doses are unlikely to induce emesis and may cause clinical signs of toxicity. Use with extreme caution, if at all, in cats. When using the conjunctival route, the eye must be thoroughly rinsed with sterile saline after emesis is achieved to prevent protracted vomiting and potential corneal irritation.
Drug interactions
May negate the emetic effects of apomorphine by blocking dopamine receptors in the CRTZ.
May cause severe hypotension; concurrent use is contraindicated in humans.
Additive CNS or respiratory depression may occur.
May reduce the emetic effects of apomorphine
Additive CNS or respiratory depression
Monitoring
- CNS status (depression or excitement)
- Respiratory rate and effort
- Heart rate and rhythm
- Vomitus (quantify volume, examine for toxic contents, and save for possible later analysis)
Pharmacokinetics
Absorption
Slowly absorbed after oral administration with unpredictable efficacy. Rapidly absorbed after IM administration (vomiting generally within 5 minutes). Topical administration to the conjunctival sac is usually effective but less so than IV or IM.
Distribution
Readily crosses the blood-brain barrier to access the chemoreceptor trigger zone.
Metabolism
Primarily conjugated in the liver.
Elimination
Excreted in the urine.
Overdose
Excessive doses of apomorphine may result in:
- Respiratory and/or cardiac depression
- CNS stimulation (excitement, seizures) or severe CNS depression
- Protracted vomiting
Treatment:
- Naloxone may reverse the CNS and respiratory depressant effects of the drug, but it cannot be expected to halt the vomiting.
- Atropine has been suggested to treat severe bradycardias associated with overdose.
- If protracted vomiting occurs from conjunctival administration, thoroughly flush the eye with sterile saline.
Available products
Formulations
- Injection
- Soluble tablets (often used for conjunctival administration or compounding)
Veterinary
- Pharmaceutical dosage forms of apomorphine have been occasionally difficult to obtain; compounding pharmacies may be required to obtain the drug.
Human-labeled
- Apomorphine HCl Injection: 10 mg/mL in 2 mL amps and 3 mL cartridges (Apokyn)
Regulatory status
POM-V
POM-V
No regulatory data for: 🇺🇸 US · 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU
Storage & stability
Store soluble tablets in tight containers at room temperature (15-30°C) and protect from light. Upon exposure to light and air, apomorphine gradually darkens in color. Do not use discolored tablets or solutions (green to turquoise). Solutions are more stable in acidic than in alkaline environments. Compounded sterile solutions (with sodium metabisulfite) can retain potency for two months at 25°C if protected from light. Do not autoclave solutions, as this causes a green discoloration.
Client information
Apomorphine is a rapid-acting medication used exclusively in a professionally supervised veterinary setting to induce vomiting after a pet has ingested a potentially dangerous substance.
- What to expect: Your dog will likely vomit within minutes of receiving the medication.
- Aftercare: Once the stomach is emptied, your pet may experience some lingering nausea, sleepiness, or lethargy.
- Important: Inducing vomiting is only the first step in treating a poisoning. Your veterinarian may recommend further treatments, such as activated charcoal or IV fluids, depending on what your pet ingested.
VetSheet drug reference is intended for licensed veterinary professionals as a clinical decision-support aid, not a substitute for professional judgement or the manufacturer’s current label.