Human Drano
Slang for Prune Juice, which helps clear up constipation quickly. Drano is a fast-acting liquid chemical used to unclog drains and pipes, such as those found in sinks. In a similar sense, prune juice is used to unclog your bowels; as such, it acts as Drano for humans, hence the name.
That Human Drano I got at the supermarket cured my constipation in about 5-10 minutes.