Anti-radiation pills were a drug to combat the effects of radiation. The Fourth Doctor gave Romana II some of the pills before venturing out onto Skaro as the levels of radiation were quite high. (TV: Destiny of the Daleks)
The Eleventh Doctor handed out anti-radiation pills to the villagers of Klimtenburg to protect them from Hapthoid radiation poisoning spread by the reactor of a crashed Cyberman ship. (PROSE: Plague of the Cybermen)