The biggest trial of quit-smoking drugs in people with mental illness was paid for by the makers
The biggest trial clearing quit-smoking pills of psychiatric harm was paid for by the two companies that make them. Both of those are true at once.
Reasonable evidence with real limitations. how we score evidence
Caveat on this rating: Funded by Pfizer and GlaxoSmithKline, the manufacturers of the drugs studied; several authors were Pfizer or GSK employees.
EAGLES randomised 8,144 smokers, roughly half of them with a psychiatric diagnosis, against nicotine patch and placebo. Neither varenicline nor bupropion produced an excess of moderate or severe neuropsychiatric events - serious mood, thinking or behaviour problems.
Having a psychiatric condition raised the event rate. The medication did not. The FDA dropped its boxed warning largely on this result.
Significant findings
Industry-funded trials reach sponsor-friendly conclusions about 1.4 times as often as independently funded ones (Lundh, Cochrane 2017).
That gap survives adjusting for how well each trial was run. Nobody falsified anything. It is the thousand small choices in designing and writing up a trial, leaning on average toward whoever paid.
Pfizer and GlaxoSmithKline employees are named authors here.
Worth asking
The design is genuinely excellent, and the evidence is still a company's evidence about its own drug. Both halves belong on the label.
If you want to quit and you take psychiatric medication, ask your prescriber what the real risk is now. Never start or stop a medication on your own.
What it is FDA approved for
Read off the label. Trial duration and approval year are shown only where they were recorded — never inferred.
- Major depressive disorder
- Prevention of seasonal major depressive episodes (seasonal affective disorder)
- Aid to smoking cessation
Source
Neuropsychiatric safety and efficacy of varenicline, bupropion, and nicotine patch in smokers with and without psychiatric disorders (EAGLES): a double-blind, randomised, placebo-controlled clinical trial — Anthenelli RM, et al. (2016)
Top-tier peer-reviewed journal
Read the source: https://doi.org/10.1016/S0140-6736(16)30272-0
DOI: 10.1016/S0140-6736(16)30272-0
How this was scored
- Study design
- Randomised controlled trial
- Funding
- Industry funded
- Published in
- Top-tier peer-reviewed journal
- Sample size
- 8,144
- Preregistered
- Yes
- Conflicts disclosed
- Yes
- Independent of proponent
- No
- Retracted
- No
Read the full scoring rubric, including what it can't tell you.
Published August 19, 2026. Last verified August 31, 2026.
Questions
How strong is the evidence behind this?
Resolv rates this source "moderate evidence". Reasonable evidence with real limitations. It scores 63 out of 100 on our published rubric. One caveat travels with that badge: Funded by Pfizer and GlaxoSmithKline, the manufacturers of the drugs studied; several authors were Pfizer or GSK employees. The score is calculated from recorded facts about the source — study design, funding, publication venue, sample size, preregistration — not typed in by an editor.
What is the source for this?
Neuropsychiatric safety and efficacy of varenicline, bupropion, and nicotine patch in smokers with and without psychiatric disorders (EAGLES): a double-blind, randomised, placebo-controlled clinical trial — Anthenelli RM, et al. (2016). Published in: Top-tier peer-reviewed journal. DOI: 10.1016/S0140-6736(16)30272-0. The full source is linked on this page so you can read it yourself.
Who paid for this research, and does that matter?
Study design: Randomised controlled trial. Funding: Industry funded. The researchers were not independent of whoever benefits from the result. Industry sponsorship is one of the most reliably measured biases in medicine, which is why funding carries real weight in the score rather than sitting in a footnote.
Is bupropion (Wellbutrin, Zyban, Aplenzin, Forfivo), wellbutrin, zyban, aplenzin, forfivo FDA approved?
Yes — FDA approved for Major depressive disorder, Prevention of seasonal major depressive episodes (seasonal affective disorder), Aid to smoking cessation. Approval is for a specific indication, not for everything the drug is prescribed for.
Is this medical advice?
This is information to bring to your prescriber, not medical advice and not a reason to change anything on your own. Nothing here is an instruction to stop or reduce a medication. If you are in crisis, call or text 988.
This is information to bring to your prescriber, not medical advice and not a reason to change anything on your own. Nothing here is an instruction to stop or reduce a medication. If you are in crisis, call or text 988.