Time Bomb was an unpleasant and lethal-sounding brew concocted by Hecuba, Queen of Time.
Hecuba served the Second Doctor a Time Bomb as part of a loathsome banquet. She claimed it was to celebrate his surviving her first round of games, but this was the only portion of her banquet that was blatantly and unquestioningly deadly. It was very green and foaming; Hecuba claimed it was made of lava from the volcanoes of Ishtar, ginseng, and a dash of lime. Her dragonlike beast-henchmen Snap and Dragon had drooled into the glasses whilst carrying them to the table. The Doctor avoided drinking his by saying it might be "too hot" for his tastes. (AUDIO: The Queen of Time)
Behind the scenes[]
"Jimson" is short for "jimsonweed", an hallucinogenic and poisonous plant.