Anticholinergic Toxicity

Aka: Anticholinergic Toxicity, Anticholinergic Poisoning, Anticholinergic Symptoms

1. Causes
   1. See Anticholinergic Medications
   2. Antihistamines
   3. Tricyclic Antidepressants
   4. Incapacitating Agents: BZ
   5. Ingested items
      1. Jimsonweed
      2. Amanita muscaria mushrooms
   6. Parasympatholytic medications
      1. Atropine
      2. Scopolamine
      3. Hyoscyamine
2. Symptoms: Mnemonic (antimuscarinic)
   1. Hot as a hare (Hyperthermia)
   2. Dry as a bone (Dry Skin)
   3. Red as a beet (Flushed)
   4. Blind as bat (Mydriasis)
   5. Mad as a hatter (Delirium)
3. Symptoms: Complete List (antimuscarinic)
   1. Altered Level of Consciousness
      1. Speech may be soft spoken, a mumbling Word Salad
      2. Hallucinations
      3. Delirium
      4. Coma
   2. Seizures
   3. Sinus Tachycardia (may approach 150 bpm in adults)
   4. Hypertension
   5. Hyperthermia (typically low grade fever)
   6. Dry Skin
      1. Examine axilla and groin (where dryness is uncommon)
   7. Dry Mouth
   8. Mydriasis with blurred vision
   9. Decreased bowel sounds
   10. Constipation
   11. Urinary Retention
4. Management
   1. Control hyperthermia
   2. Agitation may require treatment
      1. Physical Restraints
      2. Chemical Restraints (Benzodiazepines)
   3. Antidote: Physostigmine
      1. See Physostigmine for dosing and contraindications
      2. Consider Physostigmine in cases of Altered Level of Consciousness and signs of Anticholinergic Toxicity
         1. Physostigmine will transiently reverse anticholinergic effects and aid diagnosis in unclear cases
      3. Review contraindications before administration
         1. Obtain EKG prior to administration to rule out Bradycardia, intraventricular conduction delay or AV Nodal block
         2. Contraindicated in uncontrolled Asthma or Wheezing
         3. Contraindicated in Seizure disorder
   4. References
      1. Claudius and Levine in Majoewsky (2012) EM:Rap 12(5): 7