(i) LSD: It is a hallucinogen. It affects the cerebrum and sense organs, changing the feelings, thoughts and perceptions of an individual.
(ii) Morphine: It is opiate narcotic. It suppresses the normal functioning of brain and relieve intense pain but temporarily.
(iii) Barbiturates: It is a sedative and tranquiliser. It suppresses brain’s activity and creates a feeling of relaxation, drowsiness and sleepiness.