Pan-Galactic Gargle-Blaster

The Pan Galactic Gargle Blaster is an alcoholic beverage served by Milo on the Rosette of Sirius, it could apparently be used for medicinal purposes and could help cure sore throats. (COMIC: Clara Oswald and the School of Death)

Behind The Scenes
The Pan Galactic Gargle Blaster is a reference to The Hitchhiker's Guide to the Galaxy, which was written by Douglas Adams who worked on a number of Doctor Who episodes.