Caffeine (C8H10N4O2) is a purine alkaloid, colorless or white bitter crystals. It is a psychostimulant found in plants such as coffee, tea, cocoa, Paraguayan holly (mate), guarana, cola and others. The plant-based alkaloids related to caffeine are theobromine and theophylline. The fatal acute oral dose of caffeine for humans is estimated at 10-14 g (150-200 mg/kg body weight). As part of the reprofiling of drugs, caffeine is a means of oncological and radiological pharmacology.
Caffeine reduces the risk of skin cancer and melanoma, colorectal cancer developing. Depending on the dose, caffeine has a radioprotective effect, increases the sensitivity of tumor cells to ionizing radiation (the radiosensitizing effects of caffeine are associated with inhibition of the activity of protein kinases), enhances the antitumor effect of chemotherapy drugs, especially agents that damage DNA (possibly, it can help in overcoming natural drug resistance), has protective action against cytogenotoxicity caused by vinblastine.