APA Dictionary of Psychology

n. a high-potency antipsychotic of the piperazine phenothiazine class. It is as potent as haloperidol and has similar side effects, with neuromuscular and extrapyramidal symptoms predominating. Like haloperidol, it is also available in an oil-based injectable form. These so-called depot preparations are injected intramuscularly and are very slowly absorbed, allowing periods of several weeks between doses. U.S. trade name: Prolixin.