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Supplement × Prescription·Evidence index

Paroxetine and St. John's Wort: what the research found

PubMed indexes 8 records that name Paroxetine and St. John's Wort together, either in the title or in an interaction, co-administration, or pharmacokinetic context. The key findings come first, in the authors’ own words, followed by every study with its design and PubMed link.

A summary of published research, not medical advice. A pharmacist can check any combination against your full list of medicines and supplements.

Key findings

What the studies concluded.

Reviews and human studies first. Each quote is the authors’ own conclusion about their study, not a NutriStack assessment, and a single study is not a consensus.

“The antidepressants bupropion and nortriptyline aid long-term smoking cessation. Adverse events with either medication appear to rarely be serious or lead to stopping medication. Evidence suggests that the mode of action of bupropion and nortriptyline is independent of their antidepressant effect and that they are of similar efficacy to nicotine replacement.”

Hughes et al. · 2014 · Review or meta-analysis · details

“Numerous interactions between herbal medicines and conventional drugs have been documented. While the significance of many interactions is uncertain, several interactions, particularly those with St John's wort, may have serious clinical consequences.”

Izzo et al. · 2009 · Review or meta-analysis · details

“In the treatment of moderate to severe major depression, hypericum extract WS 5570 is at least as effective as paroxetine and is better tolerated.”

The research

8 studies naming Paroxetine and St. John's Wort.

Strongest relevance first: papers naming both substances in the title, then human trials and systematic reviews.

Acute treatment of moderate to severe depression with hypericum extract WS 5570 (St John's wort): randomised controlled double blind non-inferiority trial versus paroxetine.

BMJ (Clinical research ed.) · 2005 · PMID 15708844

Clinical TrialComparative StudyMulticenter StudyRandomized Controlled Trial

“In the treatment of moderate to severe major depression, hypericum extract WS 5570 is at least as effective as paroxetine and is better tolerated.”

Szegedi et al. · Authors' conclusion

Names both Paroxetine and St. John's Wort in its title.

Effects of Hypericum perforatum and paroxetine in the mouse defense test battery.

Pharmacology, biochemistry, and behavior · 2003 · PMID 12667917

Comparative StudyAnimal study

“perforatum extract. However, it should be emphasized that the risk assessment (the main index of anxiety) was not affected by the extract, while the attack reactions were only weakly modified.”

Beijamini et al. · From the abstract

Names both Paroxetine and St. John's Wort in its title.

Antidepressants for smoking cessation.

The Cochrane database of systematic reviews · 2014 · PMID 24402784

Meta-AnalysisResearch Support, N.I.H., ExtramuralSystematic ReviewHuman subjects

“The antidepressants bupropion and nortriptyline aid long-term smoking cessation. Adverse events with either medication appear to rarely be serious or lead to stopping medication. Evidence suggests that the mode of action of bupropion and nortriptyline is independent of their antidepressant effect and that they are of similar efficacy to nicotine replacement.”

Hughes et al. · Authors' conclusion

Names Paroxetine and St. John's Wort together in an interaction, co-administration, or pharmacokinetic context.

Interactions between herbal medicines and prescribed drugs: an updated systematic review.

Drugs · 2009 · PMID 19719333

Systematic ReviewHuman subjects

“Numerous interactions between herbal medicines and conventional drugs have been documented. While the significance of many interactions is uncertain, several interactions, particularly those with St John's wort, may have serious clinical consequences.”

Izzo et al. · From the abstract

Names Paroxetine and St. John's Wort together in an interaction, co-administration, or pharmacokinetic context.

Limitations

What this evidence cannot tell you.

Search-based evidence indexes have real limits, and it is worth being explicit about them:

How to read this page

A literature summary, not guidance.

NutriStack

Track what you actually take.

NutriStack is a free iPhone app for organising a supplement routine: what you take, when, and what the published record says about it. Its exploratory interaction checker covers Paroxetine, St. John's Wort, and several hundred other substances.

Log your routine, get reminders at the times you choose, and scan a label to add a product. The checker is a research and organisation tool, not a clinical decision aid.

NutriStack is an informational and organizational tool, not a medical service, and not a substitute for professional advice. Always consult a qualified healthcare professional before starting, stopping, or changing any supplement or medication.