Research and analysis

ACMD advice on 2-benzyl benzimidazole and piperidine benzimidazolone opioids

A review of the evidence on the use and harms of 2-benzyl benzimidazole (nitazene) and piperidine benzimidazolone (brorphine-like) opioids.

Documents

ACMD advice on 2-benzyl benzimidazole and piperidine benzimidazolone opioids

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Cover letter from ACMD with advice on benzyl benzimidazole and piperidine benzimidazolone opioids

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First addendum to ACMD’s report on the use and harms of 2-benzyl benzimidazole (‘nitazene’) and piperidine benzimidazolone (‘brorphine-like’) opioids, 19 December 2022

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Second addendum to ACMD’s report on the use and harms of 2-benzyl benzimidazole (‘nitazene’) and piperidine benzimidazolone (‘brorphine-like’) opioids, 6 October 2023

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Government response to the second ACMD addendum advice on nitazenes, 18 October 2023

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Third addendum to ACMD's report on the use and harms of 2-benzyl benzimidazole ('nitazenes') and piperidine benzimidazolone ('brorphine-like') opioids, 15 December 2023

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Fourth addendum to ACMD report on the use and harms of 2-benzyl benzimidazole (‘nitazene’) and piperidine benzimidazolone (‘brorphine- like’) opioids, 5 April 2024

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Government response to the ACMD's fourth addendum on nitazenes

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Fifth addendum to ACMD report on the use and harms of 2-benzyl benzimidazole (‘nitazene’) and piperidine benzimidazolone (‘brorphine-like’) opioids, 8 November 2024

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Details

This report from the Advisory Council on the Misuse of Drugs (ACMD) describes the use and harms of 2-benzyl benzimidazole (nitazene) opioids (including isotonitazene) and piperidine benzimidazolone opioids (including brorphine).

The report contains recommendations on the classification and scheduling of isotonitazene, brorphine and related substances, following a thorough review of the evidence available and using the expertise of the ACMD Novel Psychoactive Substances Committee (NPSC) members.

Since its publication in July 2022, the ACMD has published 4 addenda recommending control of newly identified 2-benzyl benzimidazole compounds by name, following detections in drug seizures and a review of their potential harms. The proposed generic definition to 2-benzyl benzimidazole variants has also been updated to capture newly identified compounds. Compounds that may appear in future and to align with international approaches. The government has provided a response to the report and subsequent addenda.

On 8 November 2024, the ACMD published a fifth addendum, recommending the proposed generic definition be further updated to capture the newly identified compound aminoisotonitazene and any structurally related compounds to it that may appear in future. This generic definition has also been expanded to capture carbamoyl derivatives of 2-benzyl benzimidazole (nitazene) opioids.

Updates to this page

Published 18 July 2022
Last updated 8 November 2024 + show all updates
  1. A fifth addendum has been added, recommending the proposed generic definition be further updated to capture the newly identified compound aminoisotonitazene and any structurally related compounds to it that may appear in future. This generic definition has also been expanded to capture carbamoyl derivatives of 2-benzyl benzimidazole (nitazene) opioids.

  2. Added the government response to the ACMD's fourth addendum on nitazenes.

  3. A fourth addendum has been added, recommending the proposed generic definition be further updated to capture the suspected newly identified compound methylenedioxynitazene and any structurally related compounds to it that may appear in future. The response to the third addendum (originally published on 21 March 2024) has also been moved to this page.

  4. Updated to include recommendation that the proposed generic definition be updated to address other structurally related compounds similar to ethyleneoxynitazene that might appear in the future.

  5. Government response to the addendum advice of 6 October published.

  6. Updated to include consideration of a further 4 newly detected 2-benzyl benzimidazole (nitazene) opioids.

  7. Added government response to the ACMD’s advice on 2-benzyl benzimidazole and piperidine benzimidazolone opioids.

  8. Updated to include consideration of a new synthetic opioid.

  9. First published.

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