The current state of knowledge on the concentration of drugs and their metabolites in the individual human body is not satisfying concerning the question about behavior of drugs in the human body, taking into account individual patient factors such as age, weight and organ dysfunctions.

This projects deals with the question of drug levels in the blood of hospitalized patients.

The aim of this study is to extend the knowledge about the behavior of drugs in the human body significantly, for the safety and benefit of future patients. This also includes to establish a relationship between drug levels in patients and the desired and undesired effects of a drug.

As a result, the future perspective is to find the optimal dose for the individual patient by measuring the blood concentration of a drug.

The primary goal of the study is to gain an overview of the plasma concentrations of relevant drugs which occur in different patient populations and to what extent they are consistent with those concentrations described in the literature.

If the expectation is confirmed, that a significant heterogeneity in the plasma concentrations of these patients exists, the investigators will try to find influencing factors for this circumstance on the basis of routine clinical parameters (height, weight, renal function, concomitant medications, etc.).

Ultimately, this project will identify substances with a high interindividual variability in plasma levels, where drug monitoring might be suggested.

Inclusion Criteria:

• legal capacity

Exclusion Criteria:

• severe anemia

Hospitalized patients