Perphenazine antipsychotic drug, molecular model. This drug, marketed as Trilafon, Triavil and Etrafon, is a common treatment for patients suffering from psychoses, including schizophrenia and manic phases of bipolar disorder. It blocks the receptors for the neurotransmitter dopamine. Although the relationship between psychoses and dopamine is not fully understood, it is thought that many symptoms are linked to an excess of dopamine. Consequently, blocking the receptors can reduce these symptoms. Atoms in this model are represented by coloured spheres; carbon is light blue, hydrogen is white, nitrogen is dark blue, sulphur is yellow, chlorine is green, and oxygen is red.