GHB (gamma hydroxybutyrate) is a depressant drug, which means it slows down messages travelling between the brain and body.
GBL (gamma butyrolactone) and 1,4-BD (1,4-butanediol) are chemicals that are closely related to GHB. Once GBL or 1,4-BD enter the body, they convert to GHB almost immediately.1
GHB usually comes as a colourless, odourless, bitter or salty liquid, often sold in small bottles or vials. It can also come as a bright blue liquid known as ‘blue nitro’, and less commonly as a crystal powder.2