Rolle des arzneimittellabors - Unerwünschte arzneimittel-wirkungen erkennen und vermeiden

The therapeutic drug monitoring (TDM) service is still the cornerstone of the drug laboratory for optimising drug therapy and avoidance of adverse drug events (ADE), although stagnation can be observed in this field. The reason for this is the use of safer drugs, simpler dosing schemes and, most importantly, a persisting lack of well conducted outcome studies, demonstrating the cost-effectiveness of this service. However, there is still a need for optimized and validated TDM guidelines in some fields of drug therapy, e.g. anticancer drugs, new immunosuppressive and antipsychotic drugs. An optimal TDM service of a competent drug laboratory includes the surveillance of the whole TDM process, including pre- and post analytical phases because a misuse of this service represents a significant drain of resources. An important responsibility of the laboratory during the post analytical phase is the evaluation of the results and the calculation of improved dosage regimens by implementation of computerized adaptive feedback concepts, which include population pharmacokinetic models and Bayesian statistical methods. This approach can also be used for optimizing the a priori dosing at the beginning of therapy in order to avoid under or overdosing for a prolonged period of time. During the recent years it has been realized that inherited variations in drug metabolism including genetic polymorphisms of drug metabolizing enzymes are an important source for ADEs and drug interactions and, thus, drug laboratories will increasingly be involved in the field of pharmacogenetic analyses. DNA chip technology, which is currently under development and will allow the simultaneous detection of thousands of single point mutations (SNPs), will further promote this field. Considering the high frequency of ADEs in hospitals any further effort to avoid ADEs will be beneficial in an overall improvement in patient care and cost effectiveness.