Can a common supplement help you quit both tobacco and weed?

NCT ID NCT04627922

First seen Jun 27, 2026 · Last updated Aug 12, 2026 · Updated 2 times

Summary

This study tested whether N-acetylcysteine (NAC), an over-the-counter supplement, can help people who use both tobacco and cannabis quit both substances. Fifty-nine regular smokers who also used cannabis took either NAC or a placebo for 8 weeks. Researchers tracked how often they used each substance and checked for abstinence using saliva tests.

What this could mean

Our plain-language read of the trial. This is informational only — not medical advice or a prediction.

Active substance
N-acetylcysteine (NAC)
What this could lead to
If it works, this could point toward a treatment for people who want to quit both tobacco and cannabis.
What could go wrong
This is a small, early-phase trial with only 59 participants. The supplement may not work better than a placebo, and results may not apply to everyone.

This is an AI summary of the original study and may miss details. Read our disclaimer.

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Conditions

The condition(s) this trial relates to.

As listed by the trial registrant

The condition terms exactly as the trial's registrant entered them.

Contacts and locations

Locations

  • San Francisco Veterans Affairs Medical Center

    San Francisco, California, 94121, United States

More trials for these conditions

Other studies related to the condition(s) this trial covers.