Nitazenes causing overdose in people who have taken fake oxycodone tablets
Source: NSW Health
Two people have been hospitalised in NSW with severe opioid overdose caused by isotonitazepyne (also known as N-pyrrolidino isotonitazene).
The fake oxycodone tablets have been described as yellow unmarked round tablets, sold as ‘OxyContin 40 mg’.
A similar yellow fake oxycodone tablet with the same nitazene was recently detected by CanTEST in Canberra.
Last Updated: 26 November 2025
Know the risks
- Fake oxycodone or OxyContin may contain nitazenes or other unexpected drugs. The tablets may be poorly made, powdery, lack markings or film coating.
- Nitazenes are synthetic opioids that are stronger and may be longer acting than many other opioids. They are up to 500 times more potent than heroin.
- Nitazenes are dangerous and vary in strength – some nitazenes are so strong that there is no safe dose. The purity can also vary within a single batch.
- The risks of overdose are increased if you:
- Use drugs alone.
- Use nitazenes or other opioids if you have not used them before.
- Use drugs again after a break.
- Use with other drugs (like alcohol, benzodiazepines, ketamine, GHB).
- Use a new batch
- Naloxone can temporarily reverse an overdose from opioids. Nitazenes may require repeated doses of naloxone. Always ring an ambulance. The effects of naloxone may wear off, and ongoing doses and hospital treatment may be needed.
- Nitazenes have also been found in benzodiazepines, vapes, heroin, ketamine, cocaine and MDMA.
- Fentanyl test strips do not detect nitazenes.
Effects to look out for
- Pinpoint pupils, drowsiness, loss of consciousness, slow breathing/snoring, and skin turning blue/grey.
- If you or others experience these symptoms, get help immediately.
Getting help
If you or your friends see the warning signs of overdose:
- Seek help immediately from your nearest emergency department or call Triple Zero (000). You won’t get into trouble for seeking medical care.
- Start CPR if someone is not responsive.
- Use naloxone if you have it. Call ‘000’ even if naloxone has been given.
Take Home Naloxone program
- Naloxone is a life-saving medicine that can temporarily reverse an opioid overdose. Naloxone is available in a very easy to use nasal spray, and as a pre-filled injection.
- You should carry naloxone if:
- you are using drugs such as opioids, cocaine, ketamine, methamphetamine or MDMA.
- you are hosting or going to a party where drugs will be present.
- If you might experience or witness an opioid overdose you can get naloxone for free without a prescription in NSW from some community pharmacies, needle and syringe programs, opioid treatment services and NUAA.
- Visit Your Room for participating sites and more information on take-home naloxone.
- NUAA can mail you naloxone in a discreet package. Order via their online shop: shop.nuaa.org.au or call (02) 9171 6650.
Support and advice
For free and confidential advice:
- Call Alcohol and Drug Information Service (ADIS) on 1800 250 015 at any time 24/7. Start a Web Chat with an ADIS counsellor Mon-Fri, 8.30am-5pm.
- Call NUAA on 1800 644 413 (Mon-Fri 9am-5pm) to speak to a peer or visit NUAA for a range of resources.
- Call the NSW Poisons Information Centre on 13 11 26 for information on adverse effects from drugs.
- Visit Your Room for a fact sheet on nitazenes.
Reproduced by permission, NSW Health © 2024