Supplement × Prescription·Evidence index
PubMed indexes 4 records that name St. John's Wort and Theophylline 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.
Every statement below is attributed to a named, dated, linked source.
This page lists published research relevant to St. John's Wort and Theophylline. 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.
Strongest relevance first: papers naming both substances in the title, then human trials and systematic reviews.
“However, no changes in the ratio of unchanged theophylline, 13U, and 3X were observed. It is unlikely that the effect of 15 days of treatment with SJW on CYPs is sufficient to cause a change in plasma theophylline concentrations.”
Names both St. John's Wort and Theophylline in its title.
“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.”
Names St. John's Wort and Theophylline together in an interaction, co-administration, or pharmacokinetic context.
“In Sweden and the UK the potential risks to patients were judged to be significant and therefore information about the interactions was provided to health care professionals and patients. The product information of the licensed medicines involved has been amended to reflect these newly identified interactions and SJW preparations have been voluntarily labelled with appropriate warnings.”
Names St. John's Wort and Theophylline together in an interaction, co-administration, or pharmacokinetic context.
Names St. John's Wort and Theophylline together in an interaction, co-administration, or pharmacokinetic context.
Search-based evidence indexes have real limits, and it is worth being explicit about them:
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, Theophylline, 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.
