It's very easy to overdose on GHB and GBL. This is because there's only a very small difference between the dose causing the desired effects and the dose leading to severe overdose.
Experienced users measure the drug out very carefully using a pipette or a syringe, or by filling pre-measured vials (small bottles) to avoid taking too much. If you don’t measure the dosage, you’re likely to overdose and fall unconscious.
Orally
Drinking GHB or GBL on its own would lead to chemical burns in your mouth and throat. Because of this, people take GHB and GBL orally by using a pipette, syringe or pre-measured vial to measure the dose and then mix it into a soft drink.
Injecting
You can’t inject GBL, but some people inject GHB – although this is rare and particularly dangerous.
Snorting
You can’t snort GBL (as it’s a liquid), but some people snort GHB powder, but this is also very rare.