Choosing the Right Dose of Antipsychotics in Schizophrenia

  title={Choosing the Right Dose of Antipsychotics in Schizophrenia},
  author={Johannes T. Tauscher and Shitij Kapur},
  journal={CNS Drugs},
Despite vast clinical experience with antipsychotics, there is no broad consensus on the doses of these substances that should be administered. Currently, most antipsychotics are administered empirically according to clinical dose-finding studies, in which arbitrarily selected doses were tested to find the ‘most efficient’ dose range in a patient population, with no regard for the molecular effects of the tested drug.Brain imaging studies using nuclear medical techniques, such as positron… 
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  • C. Tamminga
  • Psychology, Medicine
    The Journal of clinical psychiatry
  • 2003
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It is concluded that most previous animal studies of antipsychotics have used doses giving rise to inappropriately high acute D1 occupancy and inappropriately low D2 occupancy between doses, and this dosing confounder could lead to inappropriate conclusions.
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Olanzapine is a potent 5- HT2 blocker and shows a higher 5-HT2 than D2 occupancy at all doses, however, its D1 occupancy is higher than that of clozapine and similar to that of risperidone.
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Clinical doses of all the currently used classes of antipsychotic drugs cause a substantial blockade of central D2-dopamine receptors in humans, and this effect appears to be selective for the antipsychotics.
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