Experimental 'Safer Opioid' Shows Promise in Early Animal Tests

DFNZ drug provides pain relief without addiction risk or breathing suppression, NIH study finds

Apr. 9, 2026 at 7:50pm

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A highly detailed, ghostly X-ray image showing the intricate molecular structure of a pharmaceutical capsule or pill, conceptually representing the new experimental opioid drug DFNZ and its potential as a safer pain management solution.An experimental opioid alternative aims to provide pain relief without the dangerous side effects of traditional painkillers.Beverly Hills Today

Researchers at the National Institutes of Health have developed an experimental opioid alternative called DFNZ that achieved effective pain relief in mice without the typical risks associated with opioids, such as addiction potential and respiratory depression. The drug was found to increase oxygen flow to the brain rather than decrease it, and did not cause tolerance or withdrawal symptoms in the animal tests.

Why it matters

The development of a highly effective pain medication without the dangerous side effects of traditional opioids could have significant public health benefits, as the opioid crisis continues to devastate communities across the United States. If proven safe and effective in human trials, DFNZ could potentially provide a new treatment option for pain management, opioid use disorder, and other conditions currently relying on addictive and risky opioid painkillers.

The details

The DFNZ drug is a metabolite, or derivative, of a class of synthetic opioid compounds called nitazenes. Nitazenes were originally developed in the 1950s but abandoned due to their high addiction potential and overdose risk. The research team at the National Institute on Drug Abuse (NIDA) set out to decrease the potency of nitazenes and create a potential therapeutic drug. In animal studies, DFNZ provided at least two hours of pain relief in mice within just 5-10 minutes, without the serious side effects associated with typical opioids. The drug did not depress respiration or lead to tolerance, dependence or meaningful withdrawal symptoms in the tests.

  • The research findings were published in the journal Nature in April 2026.

The players

National Institute on Drug Abuse (NIDA)

A division of the National Institutes of Health (NIH) that conducted the research on the experimental DFNZ opioid alternative.

Dr. Marc Siegel

Fox News senior medical analyst who provided commentary on the dangers of nitazenes and the potential benefits of the DFNZ drug.

Dr. Hooman Melamed

A board-certified orthopedic spine surgeon and sports medicine expert in Beverly Hills, California who expressed cautious optimism about the new research but urged for more long-term data on the drug's safety and efficacy.

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What they’re saying

“Nitazenes are a dangerous group of drugs that have no medical indication and are highly addictive. They can be hundreds or thousands of times more potent than morphine.”

— Dr. Marc Siegel, Fox News senior medical analyst

“Developing a highly effective pain medication without these drawbacks would have enormous public health benefits.”

— Researcher

“DFNZ has an unprecedented pharmacology for an opioid. It is a potent and high-efficacy analgesic, but in certain contexts it resembles partial agonists, drugs that activate the receptor with low efficacy, which is what scientists think is needed for safety.”

— Dr. Michaelides, Researcher

“This new drug claims to release a lower-dose opioid alternative that might be able to offer pain relief without the addictive properties. It's also important to note that this has not been tested on humans, and we don't know how this will impact people in the long run.”

— Dr. Hooman Melamed, Orthopedic spine surgeon

What’s next

The research team plans to conduct more preclinical studies on DFNZ before seeking regulatory approval to begin human clinical trials to fully evaluate the drug's safety and efficacy.

The takeaway

The development of DFNZ represents a promising step forward in the search for effective pain relief treatments that avoid the dangerous side effects associated with traditional opioid medications. However, significant further research is still needed to determine if this experimental drug can truly deliver on the goal of providing potent pain relief without the risks of addiction and respiratory depression.