D4 antagonists

Olanzapine, sold under the brand name Zyprexa among others, is an atypical antipsychotic primarily used to treat schizophrenia and bipolar disorder. It is also sometimes used off-label in cancer patients for treatment of chemotherapy-induced nausea and vomiting and as an appetite stimulant. For schizophrenia, it can be used for both new-onset disease and long-term maintenance. It is taken by mouth or by injection into a muscle.

Buspirone, sold under the name Buspar among others, is an anxiolytic medication primarily used for the treatment of generalized anxiety disorder. Unlike benzodiazepines, buspirone does not produce significant sedation, dependence, or withdrawal symptoms.

Pimozide (sold under the brand name Orap) is a neuroleptic drug of the diphenylbutylpiperidine class. It was discovered at Janssen Pharmaceutica in 1963. It has a high potency compared to chlorpromazine (ratio 50-70:1). On a weight basis it is even more potent than haloperidol. It also has special indication for Tourette syndrome and resistant tics.

Chlorprothixene, sold under the brand name Truxal among others, is a typical antipsychotic of the thioxanthene group.

Pipamperone (INN, USAN, BAN), sold under the brand name Dipiperon, is a typical antipsychotic of the butyrophenone family used in the treatment of schizophrenia and as a sleep aid for depression. It is or has been marketed under brand names including Dipiperon, Dipiperal, Piperonil, Piperonyl, and Propitan. Pipamperone was discovered at Janssen Pharmaceutica in 1961, and entered clinical trials in the United States in 1963.

Terguride (, ), sold under the brand name Teluron, is a serotonin receptor antagonist and dopamine receptor agonist of the ergoline family. It is approved for and used as a prolactin inhibitor in the treatment of hyperprolactinemia (high prolactin levels) in Japan. Terguride is taken by mouth.

Nemonapride, also previously known as emonapride and sold under the brand name Emilace, is an atypical antipsychotic which is used in the treatment of schizophrenia. It is taken by mouth.