History
As in any patient presenting with an acute change in mental status or suspected poisoning, attempt to obtain the following information:
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Complete past medical history
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Medication history
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Precise description or sample of suspected toxicant(s)
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Route of administration, amount ingested, time since ingestion, and reason for ingestion
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Co-ingestants and use of alcohol or other street drugs
Initial signs and symptoms may include the following:
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Dry mucous membranes and skin
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Dysphagia and dysarthria
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Photophobia
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Blurred vision
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Tachycardia
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Urinary retention
Initial signs and symptoms may be followed by hyperthermia, confusion, agitation, combativeness, seizures, coma, and death. Amnesia regarding events following ingestion of tropane alkaloids is common.
Identification of ingested plants can be diagnostic of tropane alkaloid poisoning. Datura species, the most commonly encountered plants containing tropane alkaloids, are 3-5 foot annuals with coarse-toothed leaves. Trumpet-shaped flowers are 3-5 inches in length, with white-pale-violet colored petals (see the images below).
Most important for taxonomic identification are spiny, round, chambered seed pods (see the image below).
Physical Examination
The mnemonic "red as a beet, dry as a bone, blind as a bat, mad as a hatter, and hot as a hare" is useful for remembering the anticholinergic toxidrome.
Vital signs may include the following:
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Tachycardia and tachypnea
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Hyperpyrexia (in about 20% of cases)
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Inconsistent hypertension and hypotension, respiratory depression (rare)
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Warm dry skin (may be flushed)
Head, ears, eyes, nose, and throat findings include mydriasis and cycloplegia (almost always occur and may persist for days) and dry mucous membranes. Diminished bowel sounds and distention of urinary bladder may be present. Neurologic findings include the following:
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Agitation
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Confusion
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Hallucinations
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Seizures
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Decreased muscle coordination
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Paralysis
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Respiratory depression
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Coma (rare)
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Datura stramonium (jimson weed). Note 4-5 inch long white flowers.© 2000 Richard Wagner
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Datura stramonium flower. Note the trumpetlike shape.© 2000 Richard Wagner
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Datura stramonium (close-up of unripe seed pods). Note spiny appearance of pods.© 2000 Richard Wagner
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Datura stramonium is the plant shown. © 2000 Richard Wagner
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The plant shown is foxglove (Digitalis purpura), which contains cardiac glycosides, not tropane alkaloids. © 2000 Richard Wagner