Introduction. Some herbal medicinal products may be beneficial in certain respects but many can be dangerous for patients taking doctor-prescribed medications. Plant medicinal products are often taken with conventional drugs by patients. Interactions are possible between herbal medicinal products and conventional medications that can lead to toxicity due to increased drug plasma levels or drug treatment failure. Aim. The aim of the study was to review the study of plant medicinal products and drug interactions. Materials and method. Analysis of literature.