GHB(including GBL and 1,4-B) : Signs of overdose and how to respond

What is GHB, GBL or 1,4-B? 

GHB is a colourless, odourless, slightly oily liquid and is sometimes coloured with food dye. It slows the central nervous system and produces calming and slightly euphoric effects. 

GBL and 1,4-B are chemically similar to GHB and quickly convert into GHB in the body. 

Their effects come on quickly and wear off quickly, which can increase the urge to take more. Frequent use can rapidly build tolerance (needing more to feel the same effect) and physical dependence. 

Signs of a GHB overdose 

The effects of GHB vary greatly depending on dose. A very small increase can cause a “blowout” (a coma-like sleep that may last for hours) or overdose. 

GHB builds up in the body. Even after the effects feel like they are wearing off, repeated doses can build up and lead to overdose. 

The risk of overdose is much higher when GHB is taken with other depressants that slow breathing, such as alcohol, opioids or benzodiazepines. 

Signs of overdose may include: 

• Extreme drowsiness, dizziness, confusion or memory loss 

• Loss of coordination and muscle control (twitching, jerking movements or tremors) 

• Nausea, vomiting or overactive bowels 

• Irrational behaviour, severe agitation or profuse sweating 

• Irregular, shallow or slowed breathing 

• Partial or total loss of consciousness 

• Seizures or convulsions 

Note: If GHB is mixed with stimulants such as cocaine or methamphetamine, a person may display unusual or bizarre behaviour, appear agitated or irrational, and switch between alert and unconscious states. 

How to respond to a GHB overdose 

A GHB overdose can be confronting, especially if the person is behaving or moving unpredictably. 

Before you act, check for dangers and be cautious of sudden uncontrolled movements, which may accidentally cause injury. 

Check for vital signs: 

• A – Alert: Not responding to voice, touch or pain 

• B – Breathing: Noisy, shallow, slow, stopped or unusual snoring or gurgling 

• C – Colour: Blue or pale lips and fingertips (lighter skin) or grey/ashy colouring (darker skin) 

If you see any of these signs, act immediately. 

Try to get a response by calling their name and/or rubbing your knuckles firmly across their sternum. 

• If the person is responding but affected: 

• Encourage them to sit supported to avoid falls. 

• Try to keep them awake. 

• Continue assessing their responsiveness. 

• If the person is not responding: 

• Place them in the recovery position and ensure their airway is open. 

• Monitor breathing closely. 

• Vomiting can lead to choking and serious harm. 

Call an ambulance immediately if the person is unresponsive or you are concerned they may have a head injury from falling. 

What NOT to do 

• Do NOT leave the person alone – even if conscious, they are at higher risk of injury or sexual assault. 

• Do NOT give any medicine or drugs – this can increase toxicity. 

• Do NOT give anything to eat or drink – this can induce vomiting. 

• Do NOT try to make the person vomit – they could choke.