Could a person really go permanently insane from lsd?

Probably not: Further investigation into the many reports of people who developed psychosis after using hallucinogens, mostly in the 1960s, found that the overwhelming majority of these episodes resolved themselves, Flashbacks may occur. In a few cases, it was likely that the individual already had a psychotic disorder - schizophrenia, bipolar disorder or others - and the LSD pushed them over the edge.