Opium was an extract from opium poppies. It was also known as papaver somniferum, which translated to "pipe of poppy".
Opium was commonly smoked as a drug. In 1889, Li H'sen Chang smoked opium to dull the pain of his injuries. Leela thought it smelled like decaying fruit. Magnus Greel regarded Chang's men as "opium-addicted scum". (TV: The Talons of Weng-Chiang)
The woman who lodged in the rooms immediately below Lisa-Beth Lachlan smoked opium. She always placed the jar in a room near the bottom of the stairway, allowing the fumes to go up to Lisa-Beth's rooms. (PROSE: The Adventuress of Henrietta Street)