Anticholinergic Poisoning

Basics

Description

  • Anticholineric toxicity is common:
    • 15–20% of admissions for acute poisoning may be caused by anticholinergic delirium
  • Central and peripheral cholinergic blockade
  • Depending on the drug involved, antagonism occurs at muscarinic (most common), nicotinic, or both receptors
  • Onset of activity: 15–60 min after ingestion
  • Duration of effect: 2–24 hr

Etiology

  • Many drugs contain anticholinergic properties:
    • Mild at therapeutic doses
    • Life threatening in overdose
  • Agents that function predominantly as anticholinergics:
    • Atropine
    • Glycopyrrolate
    • Oxybutinin (bladder spasms)
    • Dicyclomine (IBS)
    • Scopolamine (antiemetic)
    • Benztropine (Parkinson disease)
    • Atropine and cyclopentolate (eye drops)
    • Nightshade plant species like Belladonna and Jimson Weed
  • Agents with mixed effects, including anticholinergic activity:
    • 1st-generation antihistamines (diphenhydramine, hydroxyzine)
    • Tricyclic antidepressants
    • Muscle relaxants (cyclobenzaprine)
    • Antipsychotics:
      • Typical agents: Chlorpromazine, fluphenazine
      • Atypical agents: Olanzapine, quetiapine

There's more to see -- the rest of this topic is available only to subscribers.