Due to the potent combination of anticholinergic substances it contains, Datura intoxication typically produces effects similar to that of an anticholinergic delirium: a complete inability to differentiate reality from fantasy (frank delirium, as contrasted to hallucination), hyperthermia, tachycardia, bizarre, inexplicable and possibly violent behavior, and severe mydriasis with resultant painful photophobia that renders the subject nearly blind for several days.
According to the drug information site Erowid, no other substance has received as many "Train Wreck" severely-negative experience reports as has Datura[3], noting that "the overwhelming majority of those who describe to us their use of Datura (and to a lesser extent, Belladonna, Brugmansia and Brunfelsia) find their experiences extremely mentally and physically unpleasant and not infrequently physically dangerous."