He accidentally ingested a small amount of the drug, and was thrust into a hallucinogenic experience.
It may be named after the designs on blotter paper, like Black Star, Orange Sunshine, Ying-Yang, and so on.
Flashbacks are sudden, and may occur within a few days or more than a year after LSD use.
Flashbacks are more common in people who have used hallucinogens heavily or for a long period of time, or who already have a personality or mood disorder.
Still, Hofmann could see no useful application for the drug.
United States scientists began experimenting with LSD in 1949, at first with animals. At that time, human experimentation was much less regulated than it is today, so the drug was tested widely.