Metonitazene, an analgesic compound closely related to etonitazene, was initially reported in 1957. When administered through central routes, it exhibits an astounding potency, approximately 100 times greater than morphine. However, when taken orally, its strength decreases to around 10 times that of morphine.
Its effects mirror those of other opioids, such as fentanyl and heroin, encompassing pain relief, euphoria, and sedation. Nevertheless, it’s essential to note that metonitazene use can lead to adverse effects, including vomiting and potentially fatal respiratory depression.
Due to its high potential for dependence and the grave risks associated with its use, metonitazene has never been incorporated into legitimate pharmacotherapy. Instead, it finds illicit applications in the manufacturing of counterfeit OxyContin opioid pills.

IUPAC name
CAS Number14680-51-4 
PubChem CID53316366
Chemical and physical data
Molar mass382.464 g·mol−1

Legal status

In the United States, metonitazene is classified as a Schedule I controlled substance according to the Controlled Substances Act.
While metonitazene is not explicitly regulated under the 1971 Convention on Psychotropic Substances, it’s worth noting that in various countries, the possession or intention to sell for human consumption could potentially lead to prosecution under analogue acts.


1. What is Metonitazene?

  • Metonitazene is a synthetic analgesic compound with properties similar to opioids. It is known for its potency, and it is related to substances like etonitazene.

2. Is Metonitazene legal?

  • The legal status of Metonitazene varies by country. In the United States, it is classified as a Schedule I controlled substance under the Controlled Substances Act. It is essential to check the laws and regulations in your specific region before obtaining or using Metonitazene.

3. How potent is Metonitazene compared to morphine?

  • Metonitazene is exceptionally potent. When administered through central routes, it is estimated to be around 100 times more potent than morphine. However, when taken orally, its potency is approximately 10 times that of morphine.

4. What are the effects of Metonitazene?

  • Metonitazene produces effects typical of opioids, including pain relief (analgesia), euphoria, and sedation.

5. What are the potential adverse effects of Metonitazene?

  • Adverse effects of Metonitazene use may include vomiting and, most notably, respiratory depression, which can be life-threatening.

6. Is Metonitazene used for medical purposes?

  • No, Metonitazene has not been introduced for legitimate medical use due to its high risk of dependence and dangerous side effects.

7. Why is Metonitazene associated with the illicit manufacture of counterfeit opioids?

  • Metonitazene is often used in the illicit production of counterfeit opioids, such as fake OxyContin pills, primarily due to its opioid-like effects and high potency.

8. Is Metonitazene regulated under international drug control agreements?

  • Metonitazene is not explicitly controlled under the 1971 Convention on Psychotropic Substances. However, it’s essential to be aware that in many countries, possession or intent to sell Metonitazene for human consumption could be subject to prosecution under analogue acts.

9. What are the risks associated with using Metonitazene?

  • The risks of Metonitazene use include addiction, overdose, and severe health consequences. Using this substance is highly discouraged due to its potential for harm.

10. How can I get help for Metonitazene addiction or related issues?

  • Suppose you or someone you know is struggling with Metonitazene addiction or related problems. In that case, it is essential to seek help from healthcare professionals, addiction specialists, or support organizations that can provide guidance and treatment options. Your health and safety should always be the top priority.


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