Xylazine toxicity

Background

• Also known as "Tranq"
• Analogue of clonidine and agonist at alpha 2 adrenergic receptor
• Veterinary sedative, anesthetic, analgesic, and muscle relaxant
• Human drug of abuse, usually as drug adulterant without the knowledge of people who use these drugs
  • Not an opioid, but often combined with opioids and increases the risk of overdose and death
  • Associated with complex skin infections when injected

Clinical Features

• Bradycardia
• Respiratory depression
• Hypotension

Differential Diagnosis

Sedative/hypnotic toxicity

• Absinthe
• Barbiturates
• Benzodiazepines
  • Flunitrazepam (Rohypnol)
• Chloral hydrate
• Gamma hydroxybutyrate (GHB)
• Baclofen toxicity
• Opioids
  • Lomotil toxicity
  • Loperamide toxicity
• Toxic alcohols
  • Ethanol
  • Ethylene glycol
  • Isopropyl alcohol
  • Methanol
• Xylazine toxicity

Symptomatic bradycardia

• Cardiac
  • Inferior MI (involving RCA)
  • Sick sinus syndrome
• Neurocardiogenic/reflex-mediated
  • Increased ICP
  • Vasovagal reflex
  • Hypersensitive carotid sinus syndrome
  • Intra-abdominal hemorrhage (i.e. ruptured ectopic)
• Metabolic/endocrine/environmental
  • Hyperkalemia
  • Hypothermia (Osborn waves on ECG)
  • Hypothyroidism
    • Myxedema coma
  • Hypoglycemia (neonates)
• Toxicologic
  • B-blocker
  • Ca-channel blocker
  • Clonidine
  • Digoxin toxicity
  • Ethanol
  • Opioids
  • Organophosphates
  • Xylazine toxicity
• Infectious/Postinfectious
  • Chagas disease
  • Lyme disease
  • Syphilis
• Other
  • Brash syndrome

Evaluation

• Evaluate for alternate etiologies
• Clinical diagnosis
• Consider collecting serum toxicology tests specifically for xylazine, if available (for public health reasons; does not affect acute management)

Management

• Supportive: address airway/respiratory drive/blood pressure, atropine for bradycardia
• Consider administration of naloxone due to high likelihood that opioids are also present (does not directly affect xylazine toxicity)

Disposition

• Admit if not back to baseline

See Also

• Sedative/hypnotic toxicity