Amytal, pervitin and mescaline were given to 55 schizophrenic patients, 25 of whom also received LSD. The effects were analyzed in terms of normalization and intensification of the pre-existing clinical symptoms. Amytal was classified as preponderantly a normalizer of clinical symptoms; mescaline and LSD as intensifiers; pervitin produced an unstable state with normalization and intensification being approximately equal in evidence.