Safer Using
Safer Using – Alpha-PVP
About α-PVP or “Flakka” α-PVP (pronounced alpha-PVP, short for alpha-PyrrolidinoValeroPhenone, also known as flakka, gravel, grind, the zombie drug, or…
About Nitazenes
Nitazenes, also known as benzimidazole opioids or “zenes”, are a class of synthetic opioids which vary widely in potency.1 Some nitazenes are significantly more potent than fentanyl and thus pose a very high risk of overdose.1,2 Nitazenes were first synthesised in the late 1950s but never reached the market as medicines.1 Since the early 2010s, synthetic opioids have flooded the drug market in the United States and have significantly contributed to opioid-related overdoses and deaths.2 Beginning in 2019, nitazenes have been detected in forensic laboratories across the United States, Canada, Europe and Australia.2 In 2020, synthetic opioids, including fentanyl and nitazenes, accounted for more than 60% of drug fatalities in the United States.3
In recent years, nitazenes have been detected in multiple heroin samples, counterfeit pills, and other recreational drugs across Australia. At least 17 deaths in Victoria have been attributed to nitazenes.4 In April 2024, a cluster of 20 overdoses in the blue mountains was linked to nitazenes, which the users thought was heroin.4 Across Australia, nitazenes have been detected in drugs including methamphetamine, cocaine, GHB, counterfeit Xanax alprazolam pills, counterfeit Kalma alprazolam pills, heroin, and ketamine.5-9 In the ACT, metonitazene and isotonitazepyne have been detected in separate batches of counterfeit oxycodone pills.10
Nitazene test kits are now available which can detect the presence of some nitazenes in a drug sample.11,12 These test kits are able to detect isotonitazene, protonitazene, etoniazepyne, and other nitazene analogues.11,12 However, they may not be able to detect some nitazenes such as etazene.11 They are also unable to distinguish between different analogues of nitazene. Please see here for a guide on how to purchase and use these test kits. Fentanyl test kits cannot detect nitazenes. If you are concerned your drugs may contain nitazenes, or you want to know the identity of a nitazene, consider taking a sample to a drug checking service such as CanTEST.
Nitazene Effects
The effects of nitazenes are similar to other opioids, but they can be anywhere from 3 to 1000+ times more potent than morphine.1 The effects of nitazenes can include:1,13
- Pain relief.
- Euphoria.
- Sedation.
- Sleepiness and drowsiness.
- Nausea and vomiting.
- Small pupils (miosis).
- Fever and sweating.
- Reduced stress.
- Dizziness.
- Confusion.
- Itchiness.
- Slowed breathing.
- Slowed heart rate.
- Constipation.
The effects of clonitazene typically last 4 or more hours when taken orally.14 The duration of effects may differ for other nitazenes and other routes of administration.
Nitazene Dosing
Harm Reduction
The active doses of nitazenes in humans remain largely unknown, but are all likely to be very small. The dose also depends on the exact nitazene being ingested, which is impossible to verify without access to a drug checking service. Hence, it is always recommended to start at a low dose and wait before redosing drugs (start low and go slow). The strength of a dose depends on the route of administration, with intravenous, intramuscular, and subcutaneous injection being more potent than oral administration.1
If you are using opioids for the first time, or you are using drugs that could contain nitazenes, make sure you have a friend with you who is not intoxicated, and to have easily accessible naloxone on hand. Naloxone is available either as intranasal or injectable forms, and it can be obtained for free at many pharmacies throughout Australia. It is also freely available at many needle exchanges and other Alcohol and Other Drug services.
As with fentanyls, different nitazenes can vary widely in strength, duration and onset time. Some will come on very quickly, and may work only briefly, while others may come on more gently and work for several hours. Unless you are familiar with what you are using, be very cautious. It may come on hard and fast and could last a long time (i.e., have multiple doses of naloxone ready). Always have a responsible person, and naloxone, with you when you are dosing nitazenes.
When injecting drugs, harm reduction practices can reduce the risk of vein damage, overdose, infection with blood-borne viruses (BBVs), and bacterial infection. There are many fantastic harm reduction resources for injecting drugs such as AIVL’s Vein Care Guide and The Safer Injecting Handbook. For further information you can contact CAHMA and chat with a non-judgemental health professional about vein care, naloxone, and harm reduction.
Measuring Doses
The active doses of nitazenes are often in the microgram range (< 1 milligram). Because the dose is so small, pure or semi-pure nitazene powder is extremely difficult to dose accurately. If choosing to dose a pure or semi-pure nitazene, it is recommended to use volumetric dosing. This is where a larger quantity of a nitazene is dissolved in sterile water so that a smaller dose can be taken. A guide to volumetric dosing along with a calculator are available online.
Most scales are not sensitive enough to accurately measure a nitazene dose. Gram scales, which measure tenths (0.1 g) or hundredths (0.01 g) of a gram are simply not good enough to weigh less than a milligram (< 0.001 g). A cheap set of milligram scales can theoretically weigh three decimal places (down to 0.001 g), but they will only be accurate for weighing 10 mg or more (> 0.010 g) due to the margin of error. Even if using expensive scales which can accurately weigh down to 1 mg (0.001 g), small disturbances will affect the readings, including breath, or other air movement. This means you will need to do volumetric dosing.
Dosage information is only available for clonitazene, which is approximately as follows:14
| LOW DOSE | 2.5-5 mg |
| MODERATE DOSE | 5-10 mg |
| STRONG DOSE | 10-15 mg |
For other nitazenes, there is almost no human data on the potencies or doses. Most of the existing studies compare a dose of morphine to a dose of a nitazene either in a test tube (in vitro) or in an animal (in vivo). However, the true relative potencies in humans may be much higher or lower than any of these estimates. At the very least, they provide an approximate rank ordering of the potencies of nitazenes.
Below is a table of the most common nitazenes approximately ranked from least to most potent:1,15-17
| Name of Nitazene | Approximate Potency Compared to Morphine | |
| In vitro* | In vivo** | |
| Morphine | 1x | 1x |
| Clonitazene | 3x | |
| Etazene (etodesnitazene) | > 6x | |
| Metonitazene | > 45x | |
| Etonitazepipne (N-piperidinyl etonitazene) | > 60x | |
| Protonitazene | > 200x | |
| Protonitazepyne (N-pyrrolidino protonitazene) | 350x | |
| Isotonitazene | > 350x | 600x |
| Isotonitazepyne (N-pyrrolidino isotonitazene) | > 1130x | |
| Norisotonitazene (N-desethyl isotonitazene) | > 1030x | 1300x |
| Etonitazepyne (N-pyrrolidino etonitazene) | 600x | 2000x |
| Etonitazene | 650x | 1000-2300x |
*In vitro is Latin for ‘in glass’ and means the study was performed outside of a living organism, for example in a test tube or culture dish. These results are significantly easier to acquire and are generally a good measure of relative potency between nitazenes, but may not reflect the exact potency in humans where there are many other factors such as absorption, distribution, metabolism, and excretion.
**In vivo is Latin for ‘in the living’, where results have been acquired through either human or animal studies. In vivo results are often a better measure of potency but are fewer in number than in vitro studies. The result in this table are mostly from testing in rats; hence they may not accurately translate to the potency of nitazenes in humans given differences in our biology.
These estimates demonstrate that the strongest nitazenes are: etonitazene, etonitazepyne, norisotonitazene, isotonitazepyne and isotonitazene.
In terms of dosage, these estimates suggest that for:
- Isotonitazene: 0.05 mg ≈ 30 mg morphine
- Isotonitazepyne: 0.025 mg ≈ 30 mg morphine
- Protonitazene: 0.15 mg ≈ 30 mg morphine
- Etonitazene: 0.01 mg ≈ 30 mg morphine
Active doses reported by users are in a similar range, with users suggesting that:18,19
- Isotonitazepyne (intravenous): 0.05 mg ≈ 30 mg morphine
- Protonitazene (intravenous): 0.05-0.15 mg ≈ 30 mg morphine
However, the exact nitazene they used is unverified.
If choosing to dose nitazenes, always start lower than these estimates, use with a trusted person, and carry naloxone as a precaution.
Nitazene Overdose and Naloxone
Extremely small doses of nitazenes have the potential to cause a life-threatening overdose.1 Injecting nitazenes may pose a greater risk of overdose as the lethal dose may be many times smaller than when ingested orally.1 The symptoms of a nitazene overdose can include:13
- Slow, shallow breathing.
- Snoring.
- Loss of consciousness.
- Blue or grey skin, lips, and/or fingernails.
- Small pupils.
Like fentanyl, nitazenes may also cause muscles in the chest to become rigid, which is commonly called “wooden chest syndrome”.1 This can make delivering oxygen extremely difficult, meaning they will need to go to hospital.
If you suspect someone has overdosed on nitazenes, try waking them up with a loud voice, pinching their shoulder or rubbing your knuckle over their chest. If they don’t respond, give the person naloxone and call 000 immediately. Nitazene overdoses frequently require multiple doses of naloxone and may require re-administration of naloxone at regular intervals, sometimes over several hours.
If naloxone is available, you should administer it to the person who is overdosing as soon as possible, even if you are unsure that overdose is the problem – for more information about opioid overdose and naloxone, contact CAHMA or your local harm reduction service provider.
In the meantime, if they are breathing, try to place them in the recovery position and wait with them until they recover.
If they are turning blue, or obviously not breathing, they will need oxygen or Expired Air Resuscitation (E.A.R. -otherwise known as mouth-to-mouth resuscitation).
This is fairly straightforward, but the first thing to remember is not to panic.
After calling 000, With the overdose patient on their back, the head should be tilted back slightly to open the airway. From here, pinch the nose closed and give a couple of good breaths directly into their mouth. You will need a good seal around the mouth so press firmly and exhale strongly. You should see their chest rise when this works. Often it will only require one or two breaths to get someone roused enough to breathe on their own.
If they do not start breathing by themselves, you will need to keep performing E.A.R. until help arrives; a person who is not breathing will die within three or four minutes if no oxygen (or E.A.R.) is provided.
Naloxone, also known as Narcan, is an opioid receptor antagonist which can temporarily reverse the effects of opioids.1 Naloxone can partially reverse an overdose caused by nitazenes, however, the extreme potency of synthetic opioids means that multiple administrations of naloxone are often required.1,2 Additionally, the effects of synthetic opioids typically last longer than naloxone, so the overdose may return after the naloxone has worn off.1,2 This means it is essential to seek medical attention even if you have already administered naloxone.
Naloxone is available for free without a prescription in Australia as part of the Take Home Naloxone program. Depending on the jurisdiction, it may be available at pharmacies, alcohol and drug treatment centres, needle and syringe programs, among other services. Naloxone is available for free at the CAHMA drop-in centre and at CanTEST. CAHMA runs regular Overdose Management training workshops where you can learn how to recognize the risks and signs of overdose and how to use naloxone to reverse an opioid overdose. Free take-home naloxone is provided for everyone attending these workshops. mong other services.12 Naloxone is available for free at the CAHMA drop-in centre and at CanTEST.
References
[1] https://doi.org/10.1021/acschemneuro.1c00037
[2] https://doi.org/10.1007/s40122-023-00481-6
[3] https://health.usnews.com/drugs/articles/nitazenes
[6] https://www.abc.net.au/news/2023-05-09/qld-counterfeit-drugs-opioid-police/102320078
[10] https://cantest.com.au/drug-notifications/
[11] https://doi.org/10.1186/s12954-024-01078-8
[12] https://www.drugpolicy.org.au/how_to_use_btnx_nitazene_test_strips
[13] https://adf.org.au/drug-facts/nitazenes/
[14] https://tripsit.me/factsheets/clonitazene
[15] https://doi.org/10.1007/s00204-024-03774-7
[16] https://doi.org/10.1007/s00204-022-03276-4
[17] https://doi.org/10.1016/j.drugalcdep.2023.109939
[18] https://www.reddit.com/r/Opioid_RCs/comments/1eu3iu8/megathread_isotonitazepyne_come_share_your/
[19] https://www.reddit.com/r/Opioid_RCs/comments/1eqc7ov/protonitazine_dose_thats_not_lethal/
Written by Darcy Lynch
