Using L-NAC to stop breathing problems caused by fentanyl

Repurposing L-NAC to prevent fentanyl-induced respiratory depression

NIH-funded research Case Western Reserve University · NIH-10912705

This study is looking at whether a medicine called N-acetyl-L-cysteine (L-NAC) can help people breathe better if they’ve taken too much fentanyl, while still allowing the fentanyl to work for pain relief.

Quick facts

Grant typeR21 grant
Study typeNIH-funded research
Funding institutionCase Western Reserve University NIH-funded
Lab location1 site (Cleveland, United States)
Project IDNIH-10912705 on NIH RePORTER

What this research studies

This research investigates the potential of N-acetyl-L-cysteine (L-NAC), a drug already approved for human use, to counteract the dangerous respiratory depression caused by fentanyl, an opioid pain medication. The approach involves administering L-NAC intravenously to see if it can reverse the respiratory effects of fentanyl without affecting its pain-relieving properties. The study is based on previous animal experiments that suggest L-NAC may be effective in this role. If successful, this could lead to safer opioid use in clinical settings.

Who could benefit from this research

Good fit: Ideal candidates for this research are adults over 21 years old who may require opioid analgesics for pain management.

Not a fit: Patients who do not use opioids or who are not at risk for opioid-induced respiratory depression may not benefit from this research.

Why it matters

Potential benefit: If successful, this research could provide a new way to use fentanyl safely, reducing the risk of life-threatening breathing issues in patients.

How similar studies have performed: While there have been studies on reversing opioid-induced respiratory depression, the specific use of L-NAC for this purpose is novel and has not been extensively tested.

Where this research is happening

Cleveland, United States

Researchers

About this research

  1. This is an active NIH-funded research project — typically early-stage science, not a clinical trial accepting patient enrollment.
  2. Some NIH-funded labs run parallel clinical studies or seek volunteers for related work. To check, contact the principal investigator or institution listed above.
  3. For full project details, budget, and progress reports, visit the official NIH RePORTER page below.
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.