Sedatives or Tranquillisers was a substance used to sedate individuals. (TV: The Web Planet [+]Bill Strutton, Doctor Who season 2 (BBC1, 1965).)
The First Doctor kept sedatives in his first aid box. (TV: The Web Planet)
SV90 made a sedative that Professor Til Rork used to subdue Vissey. (AUDIO: The Sentient)