Quantification of Drugs and Their Degradation Products

The study includes two study parts in which blood is collected from the patients. Study part A (observational study, already received positive ethics committee vote; Our sign: 12-330): Use of blood samples gathered during routine blood withdrawal Study part B (interventional study in the sense of additional blood samples but without an investigational product): Optional, for further pharmacokinetic questions: blood withdrawal with a maximum of 20 ml ( ten tubes of 2 ml each) within a maximal study length of four weeks. The primary objective of this study is to gain an overview about drug concentrations in plasma and/or cerebrospinal fluid (CSF), in order to determine pharmacokinetics of drugs in patients. Any drug may be tested, however the initial focus is on antiinfective, antineoplastic, and antipsychotic drugs. Many published studies show that there is a profound lack of information on pharmacokinetics and interactions of many commonly used drugs in clinical routine, and that drug concentrations, if controlled by therapeutic drug monitoring, are not in the therapeutic range (provided that such ranges are known at all).