Wiktionary
n. (context slang drug use English) A psychedelic crisis, the undesirable dysphoric psychological effects during narcotic drug use, most often fear, paranoia, and especially horrifying hallucinations
Wikipedia
Bad trip (drug-induced temporary psychosis or psychedelic crisis) is a disturbing experience typically associated with use of one or more of various hallucinogens of types including psychedelics, such as LSD, mescaline, psilocybin, and DMT, and dissociatives, such as Salvinorin A (the active chemical of Salvia divinorum) and Dextromethorphan. A "bad trip" is sometimes possible with other drugs including alcohol, cannabinoids, and MDMA.
The manifestations can range from feelings of vague anxiety and alienation to profoundly disturbing states of unrelieved terror, ultimate entrapment, or complete loss of self-identity. Psychedelic specialists in the therapeutic community do not necessarily consider unpleasant experiences as threatening or negative, instead focusing on their potential to greatly benefit the user when properly resolved. Bad trips can be exacerbated by the inexperience or irresponsibility of the user or the lack of proper preparation and environment for the trip, and are reflective of unresolved psychological tensions triggered during the course of the experience.
It is suggested that, at a minimum, such crises be managed by preventing the individual from harming oneself or others by whatever means necessary up to and including physical restraint, providing the patient with a safe and comfortable space, and supervising the intaker until all effects of the drug have completely worn off.
Usage examples of "bad trip".
This was the liberal myth -- that some drug-addled egomaniac writer from Woody Creek had run amok on horse-tranquilizers, and then laid his bad trip on the local Head population.
All you fish who want to see what a ship looks like when it comes back after a bad trip, come to Docking Station Four.
On a bad trip you only come out with mud, but Zakry pays high for mud.