Influence of the dopamine D-2 receptor (DRD2) exon 8 genotype on efficacy of tiapride and clinical outcome of alcohol withdrawal

We tested the hypothesis that allelic variants of the human dopamine D-2 re ceptor E8 genotype are associated with (i) dopamine D-2 antagonist tiapride dose in treatment of alcohol withdrawal (n = 50) and (ii) with anxiety and depression in patients during alcoholism detoxification therapy (admission n = 87; discharge n = 50). DRD2 E8 A/A genotype was associated with increa sed dose of tiapride during a 9-day detoxification therapy and with increas ed anxiety and depression scores on admission and 2 weeks later. The findin gs suggest a pharmacogenetic influence of DRD2 E8 genotype on tiapride effi cacy in alcohol withdrawal. In an earlier report, DRD2 E8 A/A genotype was associated with reduced responsiveness to the dopamine D-2 agonist apomorph ine; however, it is not clear whether both findings share the same biologic al basis. Earlier findings concerning association of DRD2 E8 A/A with incre ased anxiety and depression are replicated for the first time. Pharmacogene tics 11:647-653 (C) 2001 Lippincott Williams & Wilkins.