Answer to Quiz 2:

Ans: Anticholinergic syndrome by Jimson weed (Datura stramonium)

Discussion:

Other names: Datura Stramonium, Jimson weed, Angel’s trumpet, Apple of Peril, Jamestown weed, Thorn Apple, Talguacha.

It contains the Belladona alkaloids: Atropine (dl-hyoscyamine), Hyoscyamine, and Scopolamine (l-hyoscine).

One hundred of these seeds contain 6mg of Atropine. Other plant parts contain varying degrees of alkaloids.

It has been used since colonial times as both an herbal medicine and a drug of abuse.

Used theurapeutically as an asthama remedy or as a natural hallucinogen. May be mistakenly used in herbal teas.

The physical exam is consistent with anticholinergic poisoning.

Ingestion causes mydriasis, cycloplegia, dry skin and mucous membranes, anhydrosis, Flushed skin, Hyperthermia, tachycardia, hypertension, urinary retention, and ileus, confusion, agitation, disorientation and hallucinations.

Anticholinergic toxicity is described by the phrase,

“ As mad as a hatter,

as red as a beet,

as dry as a bone,

as blind as a bat,

and as hot as a hare.”

Onset of symptoms: 1-4 hours post-ingestion

Duration: Dose-dependent. Few hours to 2 weeks

Mechanism: Anticholinergic drugs or plants competitively bind to and block the muscarinic receptors.

Differential Diagnosis for the anticholinergic syndrome is broad and includes multiple plants (i.e. deadly nightshade), mushrooms, and drugs (i.e. diphenhydramine, phenothiazines).

A key feature that differentiates this clinical syndrome from sympathomimetic toxicity would be the absence of sweating, presence of urinary retention, and loss of bowel sounds.

Treatment:

Mildly poisoned: The majority of anticholinergic poisonings typically have good outcomes with simply supportive care along with benzodiazepines for agitation.

Moderate to Severe poisoning: In the extreme cases of poisoning with anticholinergic agents, patients can develop rhabdomyolysis, marked hyperthermia, and extreme agitation. Anticholinergic agents may also interfere with other receptors than just muscarinic receptors. For example, like cyclic antidepressants may inhibit cardiac sodium channels causing prolongation of the QRS complex, like phenothiazines may inhibit cardiac potassium efflux channels causing QT prolongation, and like diphenhydramine may inhibit histamine receptors resulting in seizures.

Treatment in such cases includes Intravenous Physostigmine (side-effect of physostigmine: seizures and dysrhythmias.

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