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

Supplement × Prescription·Evidence index

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

PubMed indexes 2 records that name Risperidone and St. John's Wort 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 Risperidone and St. John's Wort. 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

2 studies naming Risperidone and St. John's Wort.

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

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

Paliperidone poisoning and measurable plasma concentrations 2.5 years after last administered dose: A case report.

British journal of clinical pharmacology · 2025 · PMID 38450747

Case ReportsHuman subjects

“All antipsychotic treatment was discontinued after this unfortunate event, and the patient did specifically not receive any prescriptions of paliperidone or risperidone. However, the plasma paliperidone concentration was in the low end of the normal therapeutic range 2.5 years after the last dose of paliperidone was administered, and the patient still had some extrapyramidal symptoms.”

Nersesjan et al. · From the abstract

Names Risperidone 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:

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 Risperidone, St. John's Wort, 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.