A euphemism used to describe the obnoxiously fast way that a friend higher than Al Pacino on stimulants (usually amphetamine or methamphetamine) is walking ahead of you; legs fast arms slow, only a walk by definition, and at this point you have to mildly jog to keep up.
Either liquid niquil or any liquid drink with melatonin, Ashwaganda or other sleeping aids in a liquid form. If warm tea helps you get to sleep that could be sleepy juice too.
I could not sleep so I chugged some sleepy juice and now I'm so tired and sleepy.