Formulation ethnic differences

One approach to formulating potential differences in ethnic response is to examine the metabolic pathways of the common antipsychotics and determine whether the known ethnic variations in metabolizing enzymes or other effects on absorption, distribution, and excretion can be applied a priori to predict potential clinical effects. In this section we will consider some of the commonly prescribed SGAs, and only briefly touch on the FGAs. 

Dr S. Walker of CMR approached European and US companies for information on 21 drugs available in the three regions. Within this narrow sample, only one drug had genetic polymorphism, but even this did not translate to ethnic variations. Three other drugs showed regional variability in PK, but these were attributable to different formulations, different sample times and reduction of the initial dose. The CMR survey confirmed that the reported levels of adverse events were lower in Japanese patients, even when adjusted for dose - a cultural variation. 

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