Planta Med 2012; 78 - PH7
DOI: 10.1055/s-0032-1320666

Valerian: No evidence for Clinically Relevant interactions

O Kelber 1, 2, K Nieber 1, 3, K Kraft 1, 4
  • 1Working Group Efficacy, Safety and Interactions of Kooperation Phytopharmaka, Plittersdorfer Straße 218, 53173 Bonn, Germany
  • 2Scientific Department, Steigerwald Arzneimittelwerk GmbH, Havelstraße 5, 64295 Darmstadt, Germany
  • 3Institut für Pharmazie, Universität Leipzig, 04103 Leipzig, Germany
  • 4Chair of Complementary Medicine, Center of Internal Medicine, Universitätsmedizin Rostock, 18057 Rostock, Germany

In recent popular publications directed to cancer patients as well as in widely-used patient information websites (e.g. www.cancer.org or www.mskcc.org) valerian is claimed to have a potential of adverse interactions with anti-cancer drugs, thereby questioning its use (1) as a safe replacement for benzodiazepines.

Therefore a review on the interaction potential of valerian preparations was conducted.

Literature was retrieved by systematic data base search and by search in a clinical drug interaction data base (www.mediq.ch). Thereafter a systematic assessment of publications was performed.

Several in vitro studies on four CYP 450 isoenzymes, p-glycoprotein and two UGT isoenzymes could be identified. However, the methodological assessment of these studies did not support their suitability for the prediction of clinically relevant interactions. In addition, clinical studies on CYP 450 1A2, 2D6, 2E1 and 3A4 did not show any relevant interaction potential.

We therefore conclude that the interaction potential of valerian preparations, if any, is low and unlikely to be clinically relevant, suggesting that its use is safe also in cancer patients.

Literature: 1. Fernández-San-Martin et al., Sleep Med. 2010; 11: 505

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