Opium

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; Li H'sen Chang smoked opium to dull the pain of his injuries. Leela believed it to smell like decaying fruit. (TV: The Talons of Weng-Chiang)

Thomas De Quincey recorded the effect of the drug, notably hallucinations, in his book Confessions of an English Opium-Eater. (PROSE: The Banquo Legacy)

Opium could be mixed with brandy to make laudanum. (PROSE: The Eight Doctors)