Confrontation with polypharmacy in the liaison psychiatric service – Therapeutic Drug Monitoring as an opportunity?

Regarding the increasing comorbidity of somatic diseases and mental disorders not only an increase in the utilization of psychiatric liaison service can be observed but in particular an increase in polypharmacy as well. In the request for a consiliary opinion the question of the compatibility of psychotropic drugs with internal medication frequently occurs, especially in regard to drug-drug interactions. While in the inpatient treatment of psychiatric patients – but with wide regional variance – Therapeutic Drug Monitoring (TDM) is well known and part of routine clinical practice, it is very rarely used in the consultation service. This is even more disadvantageously because a huge variety of pharmacodynamic and pharmacokinetic interactions, both theoretically and practically, exist. Therefore it would be desirable also in the psychiatric consultation service to apply the TDM regularly in order to guarantee a high level of safety and good tolerability of pharmacotherapy. In the lecture, the relevant pharmacological interactions of psychotropic drugs with internal medication vice versa will be presented and discussed.