Soporific
From Tardis Wiki, the free Doctor Who reference
A soporific was a chemical that induced sleep. To access a "conference call", Madame Vastra and Jenny Flint used soporific-laced candles. They also sent a soporific candle to Clara Oswald, along with a letter laced with soporific in case she didn't use the candle. (TV: The Name of the Doctor)
