NSTK · 01.2026Independent supplement reference
NutriStack
Edition 1.0Updated August 1, 2026

Supplement × Prescription·Evidence index

St. John's Wort and Trazodone: what the published research says

PubMed indexes 3 records that name St. John's Wort and Trazodone together, either in the title or in an interaction, co-administration, or pharmacokinetic context. Each one is listed below with its study design and, where the abstract states one, the authors’ own conclusion, quoted and linked. This page reports that literature. It does not tell you whether to combine them.

Read this first

An evidence index, not guidance.

Every statement below is attributed to a named, dated, linked source.

This page lists published research relevant to St. John's Wort and Trazodone. It deliberately does not state whether the combination is safe, whether it interacts, in which direction, at what dose, or how far apart to take them.

The research

3 studies naming St. John's Wort and Trazodone.

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

Drug-drug interactions between warfarin and psychotropics: updated review of the literature.

Pharmacotherapy · 2012 · PMID 23033232

Systematic ReviewHuman subjects

“John's wort, carbamazepine, and the polycyclic aromatic carbons in tobacco cigarettes; however, nicotine itself, as in nicotine replacement strategies, is not known to alter warfarin's anticoagulant effect. In certain cases, the need for anticoagulation may also necessitate switching to a different psychotropic.”

Nadkarni et al. · From the abstract

Names St. John's Wort and Trazodone 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 St. John's Wort and Trazodone 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:

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 St. John's Wort, Trazodone, and several hundred other substances.

The checker is a research and organisation tool, not a clinical decision aid, and its per-pair assessments are excluded from search until they pass claim-level review.

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.