[en] The efficacy of radioprotector WR-2721 (300 mg/kg ip, 20 min before irradiation), alone or in combination with an extract of Ginkgo biloba (Tebonin^R) (17.5 mg/kg ip, 20 min before, and then 1 hr and 24 hr after irradiation), an extract of thymus (Thymolip^R) (10 mg/kg sc, 24 hr before and 15 min after irradiation), herbal mitogen agrostemin (0.1 mg/kg ip. 24 before and immediately after irradiation) and calcium antagonist verapamil (1 mg/kg ip, immediately before irradiation), was studied in adult male Wistar rats irradiated by 9 Gy and 12 Gy of X-rays. It was established that above mentioned compounds, except wr-2721, failed to protect irradiated animals. Given in combination with WR-2721 only agrostemin and verapamil enhanced the efficacy of the protector. The combination with verapamil was more effective providing protection even in supralethal irradiated rats. (author)