Definition
• Antagonists @ muscarinic cholinergic receptor → inhibit parasymp system
History
• Blurred vision, dry mouth, fever, AMS, flushing; “blind as a bat, dry as a bone, hot as a hare, mad as a hatter, red as a beet”
Differential
• Sympathomimetic OD, EtOH/benzo withdrawal, thyroid storm, sepsis/meningitis
Findings
• ↑ HR, ↑ temp, dilated pupils, dry MM/skin, ↓ bowel sounds, urinary retention, myotonic activity, choreoathetosis, confusion/delirium, szs
Evaluation
• ECG (≠ QTc Æ TCAs, neuroleptics); electrolytes; total CK (rhabdomyolysis); tox screen → r/o other ingestions; pulse ox; Tele
Treatment
• Supportive: IV hydration, external cooling
• Decontamination/elimination: Activated charcoal (1 dose, w/in 1–2 h), HD
• BZD (IV): For agitation, szs
• Physostigmine (IV): Reverses anticholinergic effects via acetylcholinesterase inhibition
• NOT for routine use due to risk of intractable szs, AV block, asystole
Disposition
• Admit; ICU for pts w/ cardiac instability or szs
Pearl
• Rarely fatal unless significant hyperthermia is present