Despite its early promise as 'the chemical key to schizophrenia', and its manifest properties as a psychotomimetic, LSD failed to catch on as a drug model for human psychosis. The reasons for this and the longstanding preference, instead, for the amphetamine model are examined. It is argued that the rejection of LSD was not just a scientific decision, but was influenced by increasing disaffection in psychiatry and society at large with psychological (existentialist) interpretations of schizophrenia with which LSD, as a recreational drug, was associated. The proscription of LSD and the shift towards a strongly organic view of schizophrenia created a climate where it was easier to accept the simpler amphetamine (dopamine) model. Flaws in the latter, its further recent undermining as an exclusive theory, and challenges to an overly organic psychiatry by a more psychobiological approach, are all discussed in the light of the perceived need for a more elaborated neurochemical account of schizophrenia; this includes a role for central serotonergic influences in the disorder, removing much of the previous objection to LSD as a drug model. Several ways are suggested in which data about LSD could still usefully be drawn upon in schizophrenia research; including, in animal experimentation, its direct use to test the viability of the various biological models of schizophrenia on offer. Some examples of the latter are given, including a study of LSD from the author's own past work.
