EMA: Guideline on the investigation of drug interactions
The potential for pharmacokinetic interactions between new medicinal products and already marketed drugs should be evaluated. This applies to both effects of the medicinal product on other drugs as well as the effect of other drugs on the medicinal product. Furthermore the effect of concomitant food intake needs to be investigated. Treatment recommendations are developed based on the clinical relevance of the interactions and the possibility to make dose adjustments or treatment monitoring. This document aims to provide recommendations on all these issues. General recommendations are also provided for herbal medicinal products.