Substance guides

Nitazenes: The emerging synthetic opioid threat

Published January 20, 2025 · 7 min read · Updated April 2026

Reviewed for accuracy by licensed clinical professionals.

Nitazenes are a class of synthetic opioids that are even more potent than fentanyl. Some variants are 10-40x stronger than fentanyl and have been detected in the drug supply.

What they are

A class of synthetic opioids developed in the 1950s but never approved for medical use. Multiple variants exist (isotonitazene, metonitazene, protonitazene). Some are 10-40 times more potent than fentanyl.

Why they matter

Appearing in drug supplies as fentanyl alternatives. Standard fentanyl test strips may not detect all variants. Even higher potency means even smaller lethal doses. Multiple naloxone doses likely needed for reversal.

Current status

Detected in overdose deaths in multiple US states. DEA has emergency-scheduled several variants. Detection is challenging with current field testing. Public health surveillance is tracking emergence.

Authoritative sources

This article references guidelines from: NIDA · SAMHSA · CDC

Frequently asked questions

What are nitazenes?

Synthetic opioids even more potent than fentanyl, increasingly found in the drug supply. Some are 10-40x fentanyl potency.

Can naloxone reverse nitazene overdose?

Yes, but multiple doses may be needed due to extreme potency. Always administer naloxone and call 911.

Are nitazenes widespread?

Not yet as widespread as fentanyl but detected in multiple states and expected to increase.

Disclaimer: Informational only. Not medical advice. SAMHSA: 1-800-662-4357.