To the Editor:-The following material is meant to complement Holzman's article on Atropos. Datura stramonium, from the Greek strychnomanikon (causing madness), is another of the atropine-containing herbals.
The root being drank with ye quantity of a dragm, hath ye power to effect not unpleasant fantasies. But 2 dragms being drunk, make one beside himself for three days & 4 being drank kill him. But ye remedy of this is Melicrate, much being drank, & vomited up again.
Porta's Magia Naturalis mentions the belladonna alkaloids as useful for making people "... mad for a day, without injuring their health in anyway, for the amusement of guests at feasts." 
One must be careful extrapolating animal data to humans. Cat, rat, and rabbit livers have a rapid rate of atropine metabolism. In addition, 20-25% of rabbits have an atropine esterase capable of inactivating from 1 mg to 20 mg of atropine/cm3serum. No human correlate exists. 
Atropine's mydriatric effects have been used clinically. Hughlings Jackson distinguished belladonna poisoning from postepileptic delirium by placing a drop of the patient's urine into a cat's eye. Subsequent rapid dilatation of the cat's pupil confirmed the diagnosis. Birds may not be substituted, as their irides are composed of striated muscle. 
Atropine toxicity therapy had a surreptitious origin. During medical school, Forrer saw a patient become comatose after receiving presumed procaine for local anesthesia. He later initiated atropine toxicity therapy (32-200 mg atropine sulfate, 4 days a week, for 6-30 treatments) for psychiatric therapy. Patients often had hallucinations and disturbing illusions before going into coma. Similar treatments were also used for Parkinson disease, with up to 195 mg hyoscine (scopolamine) used. 
In 1700, the founder of American psychiatry dealt with Datura. Sixty years later, Storck hinted at the psychiatric use of Datura:
If the thornapple, by disordering the mind, causes madness in sound persons, may we not try whether, by changing and disturbing the ideas and common sensory, it might not bring the insane, and persons bereft of their reason, to sanity, or soundness of mind, and, by a contrary motion, remove convulsions in the convulsed. 
The classic description of anticholinergic poisoning is: "hot as a hare, blind as a bat, dry as a bone, red as a beet, and mad as a hen." 
Several of Datura nicknames have dark overtones: Devil's apple, Devil's trumpet, herbe aux sorciers au de diable. 
Gerard notes that Datura is "of greate use in surgery" and "of a drowsie and numming, qualitie, not inferior to Mandrake." He also relates Theocritus' observations: "... even all the Colts and agile Mares in mountains mad do fall." 
David C. Lai, M.D.
Visiting Instructor; Department of Anesthesiology; University of Rochester Medical Center; Rochester, New York; email@example.com; Currently: Instructor in Anaesthesia; Harvard Medical School; Attending Faculty in Anaesthesia; Beth Israel Deaconess Medical Center; Boston, Massachusetts; firstname.lastname@example.org
(Accepted for publication February 6, 1999.)