The results indicate that TPMT genotype influences the safety and efficacy of ALL treatment and genotype information may therefore be useful for optimizing 6-MP therapy.

The prevalence of polypharmacy in Poland is similar to that reported in other countries. This may suggest that, in a substantial proportion of schizophrenic patients clinical response to the antipsychotic monotherapy is unsatisfactory. Further studies focusing on the efficacy and safety of strategies in the treatment of patients with schizophrenia not responding to antipsychotic monotherapy are necessary.