June 19, 2024

Nitazenes: 101

You’ve heard of opioids, and you may know the common ones: heroin, oxycodone, morphine or fentanyl (among others). Opioids are a class of naturally occurring and synthetic substances derived from the opium poppy. These substances bind to the opioid receptors in the brain which slow down the signals between the central nervous system and the brain and releases dopamine.  These substances slow down the transmission of pain signals, resulting in relief from pain and euphoria. Read more about opioids here. As new synthetic opioids emerge, called Nitazenes, safety concerns are rising, along with the rates of overdose. So, what are nitazenes and what impact are they really having?  


What are Nitazenes? 

Nitazenes are a class of synthetic opioids, which means they are artificially created to mimic the effects of substances derived from the opium poppy. Originally synthesised in the 1950s as an alternative to morphine, nitazene was never approved for therapeutic use, due to safety concerns over the high risk of overdose. There are many different nitazene compounds, including but not limited to; protonitazene, isotonitazene, metonitazene, etodesnitazene, butonitazene and clonitazene.  


Opioid strengths 

A substance’s strength or potency can be difficult to quantify, particularly when purchased from the black market, as different batches will have varying compositions. However, the following guide provides an approximation for different opioids and their strengths. 

Heroin can be 2-4 times more potent than morphine 

Fentanyl can be 50-100 times more potent than heroin 

Nitazenes can be 50 times more potent than fentanyl and 500 times more potent than heroin 


Effects of Nitazenes 

The effects of nitazenes can vary but the main effects are pain relief, euphoria, sedation and drowsiness, nausea/vomiting and respiratory depression. Nitazenes can affect breathing more than other opioids and overdose can last longer than other opioids. Because of this, nitazene overdoses often require more naloxone than other opioids.  


Where have Nitazenes been found?  

Nitazenes have been detected across Australia in a range of substances including:  

  • Black market vape juice

          Drug Alert here:

  • Substances sold as heroin  

          Drug Alert here:

  • Fake Benzodiazepines: 

          Drug Alert here:

  • Substances sold as MDMA:

Drug Alert here:

  • Nitazenes have also been detected as a yellow powder 

          Drug Alert here:

  • There have also been reports of Nitazenes showing up in ketamine, cocaine, oxycodone, and synthetic cannabinoids  


Risks of overdose 

Some nitazenes are so strong that there is no safe dose, and even people with current experience of opioid use are at risk of experiencing an overdose. This overdose risk is significantly increased for people with no known experience with opioids, who may unknowingly consume nitazene as an adulterant in another substance.  

Risks of overdose are increased if you: 

  • Use drugs alone 
  • Use drugs again after a period of not using   
  • Use nitazenes if you have not used opioids or do not use them regularly.  
  • Use a new route of administration eg. going from snorting to injecting  
  • Use a new batch  
  • Mix with other opioids or downers such as alcohol, ketamine, benzodiazepines or GHB 


Effects to look out for  

  • Loss of consciousness  
  • Inability to be roused by calling their name or a firm shoulder squeeze 
  • Pinpoint pupils 
  • Skin around the mouth and fingertips turning blue (lighter complexions) or grey (darker complexions) 
  • Slow / shallow / strained breathing  
  • Deep snoring or gurgling    


Keeping yourself safe 

  • Avoid using drugs alone  
  • Always tell someone what you have taken  
  • Start with a low dose and re-dose slowly with smaller amounts  
  • Avoid mixing with alcohol and other drugs 
  • Be aware that fentanyl test strips will NOT work on nitazenes 



Naloxone is a lifesaving medication that can temporarily reverse the effects of an opioid overdose. Naloxone is available as a nasal spray that contains one dose and a pre-filled injection that contains 5 doses. As an opioid antagonist, naloxone’s only function is to block the effects of an opioid overdose, making it safe to administer in all cases of a suspected opioid overdose. Due to nitazenes’ strength, multiple doses of naloxone may be required.  

If you are at risk of experiencing or witnessing an opioid overdose, you can get Naloxone for FREE without a prescription at any ACON office via their NSP, as well as some pharmacies, needle and syringe programs and NUAA. Naloxone is available as a nasal spray and a pre-filled injection.  

Visit Your Room here to find a participating take home naloxone program or get more information.  


Learn more about Nitazenes here.

Learn more about opioids from Touchbase and DanceWize.

All NSW Health Drug Warnings, can be found here.