Schlaftrunk (pronunciation: SHLAAF-troonk; Germ. "sleeping potion") is a potion used by Grimms for putting Wesen to sleep.

It is very effective even in tough Wesen such as the Siegbarste, and can be administered to a Siegbarste by filling an arrow with it to be shot into his neck. It is an extremely potent toxin and a few drops can be very effective against most Wesen.