Bad trip

Japanese: bad trip（英語表記）badtrip

...Its psychological effects do not simply cause hallucinations, but also have a psychedelic effect that makes people aware of a second self that they had never known before. In the 1960s, it was popular among young people, mainly in the United States, and it is said that 35% of American university students had taken it. If the environment in which it was taken was bad, it could cause people to go into a state of panic, resulting in them jumping off buildings or committing murder, which became a social problem. It was erroneously reported that it caused chromosomal abnormalities, and its use was banned worldwide in 1966. ...

From [Hallucinogens]

...After taking the drug once, 25% of people experience a flashback phenomenon in which the same mental state as when they first took the drug occurs several weeks or months later, but this subsides within a few minutes. After taking the drug, some people may experience a state of panic (called a bad trip), but this can often be calmed down by persuasion. Even if this persists, the condition returns to normal within six weeks. ...

*Some of the terminology that mentions "bad trip" is listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

Japanese:

…その精神作用は，単に幻覚をおこすだけではなくて，いままで知らなかった第2の自己に気づかせるという精神展開作用psychedelic effectをも示すので，1960年代に主としてアメリカで，若者たちに愛用され，服用経験者はアメリカの大学生の35％にのぼったという。服用の環境が悪いと恐慌状態bad tripに陥り，ビルから飛び降りたり殺傷事件をおこしたりすることから，社会問題になった。染色体異常をおこすと誤報されて，66年に世界中で使用が禁止された。…