Flupentixol use and adverse reactions in comparison with other common first- and second-generation antipsychotics: data from the AMSP study

This study compares the first-generation antipsychotic (FGA) flupentixol to haloperidol and common second-generation antipsychotics (SGAs) as to drug utilization and severe adverse drug reactions (ADRs) in clinical treatment of schizophrenia inpatients using data from the drug safety program Arzneimittelsicherheit in der Psychiatrie (AMSP). AMSP drug utilization and reported ADR data were analyzed. Type and frequency of severe ADRs attributed to flupentixol were compared with haloperidol, clozapine, olanzapine, quetiapine, risperidone and amisulpride in a total of 56,861 schizophrenia inpatients exposed to these drugs. In spite of increasing prescription of SGAs, flupentixol was consistently used in schizophrenic inpatients (about 5 %) over time. Reporting rates of severe ADR ranged from 0.38 to 1.20 % for the individual antipsychotics (drugs imputed alone); flupentixol ranked lowest. The type of ADR differed considerably; as to severe EPMS, flupentixol (0.27 %), such as risperidone (0.28 %), held an intermediate position between haloperidol/amisulpride (0.55/0.52 %) and olanzapine/quetiapine (< 0.1 %). The study is a heuristic approach, not a confirmatory test. Flupentixol has a stable place in the treatment of schizophrenia in spite of the introduction of different SGAs. Comparative ADR profiles suggest an intermediate position between FGAs and SGAs for flupentixol in clinical practice.