Table 2. Major classes of drugs developed to treat psychiatric disorders.

NE, norepinephrine; 5-HT, 5-hydroxytryptamine (serotonin); GABA, γ-aminobutyric acid.

Drug classPrototype compoundMolecular target(s)
Mood stabilizerLithium (Li+)GSK3β, inositol 1-phosphatase*
Antipsychotic drugsChlorpromazineDopamine D2 receptor
AntidepressantsIproniazid, ImipramineMonoamine oxidase, NE, and 5-HT transporters
Benzodiazepine receptor agonistsChlordiazepoxideGABAA receptor, benzodiazepine site

*Although much research favors GSK3β (glycogen synthase kinase β) as the relevant target of Li+, the drug’s mechanism of action remains uncertain.