GHB (Gamma-hydroxybutyrate)

A powerful depressant drug. GHB appears as a clear oily liquid with no smell and can be tasteless or quite salty. Sometimes GHB can appear cloudy. 

Also known as: G or Gina

Usually, GHB comes in liquid form but can also come in the form of a powder or capsule (CAMH, 2013). GHB causes the user to experience sexual arousal, muscle relaxation, and euphoria, but the effects of GHB can differ drastically depending on dosage (Giorgetti et al., 2017; Hillebrand et al., 2008). In greater doses or when used with other depressants like alcohol, GHB can have serious and life-threatening adverse effects (Hillebrand et al., 2008).

At low doses, the effects of GHB are similar to the effects of alcohol, increasing sociability, reducing inhibitions, and producing euphoria (Hillebrand et al., 2008).


While the GHB is sought after for its desirable effects, the effects are dose-dependent (Hillebrand et al., 2008). A slightly greater dosage can cause serious and life-threatening adverse effects that may include:

  •       Light-headedness or dizziness.
  •       Irritability and/or aggressive behaviour.
  •       Slowed and/or cessation of breathing.
  •       Lowered heart rate.
  •       Nausea and/or vomiting.
  •       Loss of consciousness.
  •       Seizure.
  •       Coma.


Aside from dosage, the effects of GHB can vary person-to-person depending on the frequency of use and if GHB is used with other substances (CAMH, 2013). Other factors that impact GHB effects include:  

  •       Individual factors (e.g., age, weight, comorbidities)
  •       Environmental factors (e.g., the setting/location)


Like most substances, regular or long-term use of GHB can lead to dependence. Cessation of GHB use when a dependence has formed can cause dangerous withdrawal effects (Bell & Collins, 2011). The withdrawal effects of GHB may vary based on history of use, but generally include:

  •       Anxiety.
  •       Tremor.
  •       Sweating.
  •      Nausea and/or vomiting.
  •      Headache.


More severe withdrawal effects that may be life-threatening include:

  •       Increased heart rate and blood pressure
  •       Seizures.
  •       Confusion.
  •       Rhabdomyolysis.


Service Provider Tip: Discontinuing GHB use suddenly after prolonged use can be dangerous. Encourage guys to seek guidance from a medical professional if they wish to reduce or discontinue their GHB use.

The onset of GHB effects usually begin around 15 minutes after use and last for approximately 3-4 hours (Hillebrand et al., 2008).


The effects of GHB are dose-dependent, meaning that a euphoric dose for one user may be a sedative dose for another user, leading to serious or adverse effects (Hillebrand et al., 2008). As a general dosage guideline, 0.5g may cause the user to experience relaxation and disinhibition, 1g may cause the user to experience euphoria, and 2-3g will likely lead to adverse effects (Hillebrand et al., 2008). 


Service Provider Tip: For safer use, encourage guys to wait for the onset of effects from an initial dose of GHB before taking a second dose. Taking slightly greater amounts of GHB can lead to adverse effects including sleepiness, slowed breathing and heart rate, and/or coma (Hillebrand et al., 2008).

Service Provider Tip: To promote safer use of GHB, encourage guys to refrain from using other substance while using GHB, especially other depressants like alcohol (Hillebrand et al., 2008). Guys should also be encouraged to use measuring devices to ensure they know how much they are using.


Prescribed Substances

GHB can produce serious and life-threatening adverse effects when used with certain HIV medications.


HIV Medications

  • Ritonavir and Cobicistat are used to boost the availability of other substances (primarily other HIV medications) in the body by decreasing the breakdown of these substances (CAMH, 2013).
  • Ritonavir and Cobicistat interact with GHB by increasing the availability of GHB in the body, leading to adverse effects (Lee et al., 2021).
  • Interactions with GHB have been observed with the Cobicistat-Boosted Elvitegravir regimen (Lee et al., 2021).
  • There is potential for the Atazanavir HIV medication to interact with GHB (Lee et al., 2021).


Recreational Substance

When GHB is used with other recreational substances this can lead to serious or life-threatening adverse effects.



  • Combining GHB and alcohol can cause a sedative effect, causing breathing to slow down, loss of consciousness, coma, and potentially death (Giorgetti et al., 2017)



  • Benzodiazepines prescription depressant medications but are frequently used in recreational settings.
  • Benzodiazepines are depressants which can exacerbate the effects of GHB leading to serious and life-threatening adverse effects (Hillebrand et al., 2008).

Recently, Canada passed the “Good Samaritan Drug Overdose Act.” This means that if police attend a 911 call for an overdose and there are drugs present, anyone in attendance is protected against simple drug possession charges, even if they’re on probation or parole. See this helpful info by the HIV Legal Network. You can download a PDF of it [here].

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