GHB, GBL and 1,4-BD usually come in a colourless liquid, often sold in small bottles or vials, less often in a crystal powder or tablet. Effects are usually felt within 10-20 mins and full effects in 45-90 mins. GHB has almost no smell and a salty/soapy taste, GBL has a strong chemical taste and smell, and 1,4-BD has a bitter-sweet taste. GBL and 1,4-BD are chemicals closely related to GHB. Once GBL or 1,4-BD enter the body, they convert to GHB almost immediately – be cautious as these chemicals can be stronger and easier to overdose on. Usually swallowed, sometimes injected or plugged.

This is a guide only – know more, be safer.

Effects on the Brain

How GHB/GBL makes you feel

Depends on how you feel before you use GHB/GBL, and the surroundings you’re in. You can feel happy, relaxed, drowsy, confused, anxious, or paranoid. Smaller doses may feel more stimulating and higher doses may feel more sedative. 

Effects on the Body

What GHB/GBL does to your body

You might experience an increased sex drive, sweating, lowered inhibitions, dizziness, tremors, slowed breathing, ringing in the ears, blackouts, memory loss, muscle twitches, nausea and diarrhoea. 

Drug Duration Calculator
Staying Safe

How long does GHB/GBL last?

Effects last
Can last 1.5-5 hours
Stays in your system for
In system
Saliva test: not detectable by saliva test. Urine test: Up to 12 hours
No longer detectable in your system
+12 hours

Depends on:

Depends on:

  • Your Size/Weight
  • Tolerance to the drug
  • Drug Strength
  • Type of test. These time frames are based on saliva and urine drug tests. Testing equipment can vary - this is a guide only.

How do you stay below 0.05? (This is a guide only)

Men average size: No more than 2 standard drinks in the first hour and 1 drink per hour after that.

Women average size: No more than 1 standard drink per hour.

Mixing Substances

Risks of mixing GHB/GBL with other substances

Mixing GBH/GBL with other drugs can have unpredictable effects and increase the risk of harm.

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Lower Risk Substances

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Moderate Risk Substances

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High Risk Substances

Potential Side Effects

When you take too much GHB/GBL



Irregular or shallow breathing




Risk of death

Staying Safe

Risks when taking the substance

  • Small increases in dose can result in big increases in effect, and overdose can happen easily.
  • The strength of these drugs varies - it’s easy to take too much. The difference between the amount needed to get high and the amount that causes an overdose can be hard to judge.
  • The doses for GHB and GBL and 1,4-BD are very different.
  • GBL and 1,4-BD can be stronger and easier to overdose on.
  • Long-term use can result in memory problems, heart disease, hallucinations, extreme anxiety and breathing problems.
  • Giving up GHB after using it for a long time is challenging, always talk to a medical professional if you’re planning to stop using - sudden withdrawal can be dangerous.
  • Small increases in dose can result in big increases in effect, and overdose can happen easily.

Staying Safe

Harm reduction

  • Research safe dose
  • Always take a small amount first and wait to feel the effects of GHB (a couple of hours) before using more
  • A plunger can help to measure your dose
  • Eat before using
  • Avoid using alone
  • Use with people you trust and in a safe place
  • Avoid frequent and regular use
  • Drink water to prevent dehydration