Aripiprazole and haloperidol: beneficial combination antipsychotic therapy for a schizophrenic patient.

Abstract Objective:Schizophrenia is a chronic disease that is treatedwith dopamine antagonists. These drugs can pro-duce intolerable side effects through their block-ade of central nervous system dopamine receptorsunrelated to schizophrenia. The atypical antipsy-chotic aripiprazole, a dopamine receptor partialagonist, has mixed agonist-antagonist effects. Itspartial agonism is said to protect the patient fromthe side effects caused by full antagonists at thesame time that its antagonism treats the schizo-phrenia effectively.Case:We report a case in which a low dose of thefull antagonist haloperidol, added to aripipra-zole, improved antipsychotic efficacy in a 41-year-old man diagnosed with undifferentiatedschizophrenia.Result:A 15-mg/d aripiprazole/7.5-mg/d haloperidolregime in this patient improved all previouspsychotic symptoms and caused no adverse sideeffects. The patient’s final prolactin concentrationusing this combination was normal.Conclusion:Further studies are warranted to confirm thisobservation and to determine the mechanismthrough which a carefully titrated combination ofa full antagonist with a partial agonist can causesuch improvement.Key Words: aripiprazole, partial agonist,haloperidol, schizophrenia