The article describes a study of the protective effect of dandelion (Taraxacum officinale L. Asteraceae) in combination with two xenobiotics: ciprofloxacin and pyralene. For that purpose, methanolic extracts of the plant flower, leaf, stem, and root upon removal of the solvent were successively extracted with ether, chloroform, ethyl acetate, and n-butanol. The extracts were evaporated to dryness and then dissolved in 50% ethanol to obtain 6% (w/v) solutions. These solutions, either alone or in combination with different doses of ciprofloxacin or pyralene, were used to study their effect on liposomal lipid peroxidation (LPx) induced by Fe 2+ and ascorbic acid. It appeared that almost all the individual extracts exhibited an antioxidant effect and in combination with pyralene decreased its pro-oxidative action on liposomal LPx. At lower concentrations, ciprofloxacin alone did not exhibit an antioxidant effect, but at higher concentrations it acted as a pro-oxidant, the effect being lowered by the presence of dandelion extracts. It is interesting to note that the extract of dandelion stem exhibited a very strong protective effect
