We discussed a case of a patient with no significant past medical history, who presented with acute seizure-like activity and acute encephalopathy, found to have tachycardia, mydriasis, sluggish pupillary accommodation to light, and urinary retention, due to Anticholinergic overdose. It was discovered that they took > 100 tablets of Benadryl.
Initial evaluation of various toxidromes should be based on clinical findings (vital signs, eyes, skin/secretions, mental status)
Anticholinergic toxicity affects can affect peripherally, centrally, or both.
Treatment
- Ensure ABCs are intact
- Cardiotoxicity: sodium bicarb can be used if widened QRS (>100 ms)
- Decontamination: activated charcoal can be used if the patient presents within the first 2 hrs
- Seizures / agitation: treat with ativan
- Physostigmine: may be used if there is both peripheral and moderate central anticholinergic toxicity, but should NOT be given if the QRS is > 100ms or in TCA overdose