Anticholinergic toxicity

• Anticholinergic toxicity:

  • Can occur when taking typical or atypical antipsychotics
  • Important to consider anticholinergic toxicity in patients taking multiple medications
  • Clinical diagnosis
• Clinical features:

  • Red as a beet - flushing
  • Dry as a bone - anhidrosis, dry mucous membranes
  • Blind as a bat - mydriasis (dilated pupils)
  • Mad as a hatter - delirium, hallucinations, agitation. Seizures and jerking movements are also possible
  • Hot as a hare - fever
  • Full as a flask - urinary retention
  • Decreased bowel sounds are commonly found on exam
• Management is mostly supportive care:

  • Activated charcoal - if ingested within 1 hour
  • Agitation may be treated with benzodiazepines
  • IV fluids - hypotension or rhabdomyolysis
  • Cooling measures for hyperthermia
  • IV sodium bicarbonate can be administered if wide-complex arrhythmias develop
  • Physostigmine - acetylcholinesterase inhibitor - only administer with resuscitation equipment present
• Complications:

  • Respiratory failure
  • Cardiovascular shock
  • Rhabdomyolysis
  • Seizures
  • Coma
  • Death