February 11, 2021

All about G: What’s the difference between GHB, GBL, and 1,4-BD?

Pivot Point has heard anecdotal reports of an increased presence of GBL and 1,4-BD in substances sold as GHB (or G) in Sydney. We’re here to help you understand what that means, and how that might affect you.


What is GHB?

GHB (gamma hydroxybutyrate) is a central nervous system depressant. This means it slows down the messages travelling between the brain and the body. It usually comes as a colourless and odourless salty tasting liquid. It sometimes comes as a blue liquid and rarely in tablet or powder form.

GHB is usually swallowed but some people shelve/booty bump G.

Read more about GHB and how to avoid the ‘drop zone’.


What is GBL or 1,4 BD?

GBL (gamma butyrolactone) and 1,4-BD (1,4-butanediol) are chemicals that are closely related to GHB. They are often known as ‘precursors’ to GHB, because they convert to GHB in the body. They are industrially used as a paint stripper or solvent.

Both GBL and 1,4 BD are often sold as GHB, and because they convert to GHB in the body, can have similar effects. Both GBL and 1,4-BD have a stronger chemical taste than GHB. 1,4-BD has a melting point of 20.1 degrees, which means it will thicken when put in the fridge.


Why is this important?

Because GBL and 1,4 BD are precursors (also known as prodrugs) to GHB, they have to convert to GHB in the body. This makes them potentially stronger and more unpredictable. GBL, 1,4-BD and GHB all have different potency and onset times.

GBL is generally stronger than 1,4-BD and GHB, which means you need less of it. It generally has a faster onset time than GHB, while 1,4-BD has a slower onset time than GHB. The speed at which you feel the effects can be impacted by a number of factors, including your metabolism, tolerance, and the purity or strength of the GHB/GBL/1,4-BD.

Often in Australia, GBL and 1,4-BD are sold as GHB or simply just as G, so it’s difficult to know exactly what you’re taking and how it will affect you. Some of these descriptors may help you identify which substance you have, but they may not always be accurate. Start with a small amount, and always wait until you feel the effects before dosing again. Because GHB has a steep dosage response, a tiny increase in dose can cause a big increase in effects, especially if you’re taking GBL or 1,4-BD when you think it’s GHB.


Be aware that if you’re taking G, it might be GHB, GBL, or 1,4-BD. This will impact how strong the effects are, and how long you will take to feel them. Whether it’s GHB, GBL, or 1,4 BD, G should never be mixed with alcohol or other depressants.

For more information about reducing the harm of GHB, GBL, and 1,4-BD, head to our resource directory.