Matricaria recutita (Chamomile) is one of the most important and oldest medicinal plants known to man in the world. The main origin and center of the gene pool of this plant is the Mediterranean region, especially Iran. The aim of this study was to investigate the drug interaction of chamomile with routine chemical drugs. Consumption of chamomile with anticoagulants, sedatives, drugs requiring GI absorption, and iron supplementations causes drug interactions. Concomitant use of chamomile with these chemicals should be used with caution to prevent drug interactions and side effects.