UMEM Educational Pearls

Title: Altered Mental Status- Is It Anticholinergic Toxicity?

Keywords: Anticholinergic, Beers Criteria, mushrooms (PubMed Search)

Posted: 6/7/2017 by Jon Mark Hirshon, PhD, MPH, MD
Click here to contact Jon Mark Hirshon, PhD, MPH, MD

A patient presents with altered mental status for unclear reasons- could it be anticholinergic syndrome?

There are many medications (e.g. Beers Criteria, see pearl from March 5, 2017) and plants (e.g.: certain mushrooms) that can cause this life-threatening toxidrome.

The quick mnemonic for anticholinergic poisoning is:

· Hot as a hare (hyperthermia)

· Red as a beet (flushed)

· Cry as a bone (decreased secretions)

· Blind as a bat (mydriasis)

· Mad as a hatter (delirium)

· Full as a flask (urinary retention)

Bottom line: Keep anticholinergic syndrome within your differential for a patient with altered mental status without a clear cause.

Note: An earlier version of this pearl incorrectly listed organophospahtes, which cause cholingeric toxicity.

Additional Information

The clinical manifestations of anticholinergic syndrome can be extensive. Additional symptoms can include:

· “Sinus tachycardia

· Decreased bowel sounds

· Functional ileus

· Urinary retention

· Hypertension

· Tremulousness

· Myoclonic jerking

Patients with central anticholinergic syndrome may present with the following:

· Ataxia

· Disorientation

· Short-term memory loss

· Confusion

· Hallucinations (visual, auditory)

· Psychosis

· Agitated delirium

· Seizures (rare)

· Coma

· Respiratory failure

· Cardiovascular collapse”¹

References

1) http://emedicine.medscape.com/article/812644-overview

2) http://www.uptodate.com/contents/anticholinergic-poisoning