K. Rieger

Undeclared exposure to St. John's Wort in hospitalized patients.

W. Haefeli, I. Walter‐Sack, J. Burhenne, 2004, British journal of clinical pharmacology.

Simultaneous determination of hypericin and hyperforin in human plasma with liquid chromatography-tandem mass spectrometry.

W. Haefeli, G. Mikus, J. Burhenne, 2004, Journal of chromatography. B, Analytical technologies in the biomedical and life sciences.

A systematic comparison of four different workup procedures for systematic toxicological analysis of urine samples using gas chromatography–mass spectrometry

W. Haefeli, F. Peters, H. Maurer, 2009, Analytical and bioanalytical chemistry.

Objective assessment of nonadherence and unknown co-medication in hospitalized patients

W. Haefeli, M. Meyer, I. Walter‐Sack, 2012, European Journal of Clinical Pharmacology.

High prevalence of unknown co-medication in hospitalised patients

W. Haefeli, I. Walter‐Sack, M. Martin-Facklam, 2004, European Journal of Clinical Pharmacology.

Objective assessment of nonadherence and unknown co-medication in hospitalized patients

W. Haefeli, M. Meyer, I. Walter‐Sack, 2012, European Journal of Clinical Pharmacology.