Is it safe to mix St. John's Wort (Hypericum perforatum) with coffee?

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From the Guidelines

Mixing St. John's Wort with coffee is not recommended due to potential interactions that may increase the risk of adverse effects such as anxiety, jitteriness, and insomnia. When considering the combination of St. John's Wort and coffee, it's essential to understand the potential interactions between these two substances. St. John's Wort (Hypericum perforatum) is an herbal supplement known to affect serotonin levels and liver enzymes, which can influence the metabolism of various substances, including caffeine found in coffee 1. On the other hand, coffee contains caffeine, a stimulant that affects the central nervous system, and its effects can be altered by the concurrent use of St. John's Wort.

The primary concern with combining St. John's Wort and coffee is the potential for increased side effects. St. John's Wort may enhance the clearance of certain substances, including potentially altering how the body processes caffeine, leading to increased levels of caffeine in the system, which can exacerbate anxiety, jitteriness, increased heart rate, and insomnia 1. Additionally, both St. John's Wort and coffee can cause gastrointestinal discomfort, and their combined use might worsen these effects.

Given the potential for adverse interactions, it is advisable to separate the consumption of St. John's Wort and coffee by at least 2-3 hours to minimize potential interactions. Individuals with anxiety disorders, heart conditions, or sleep problems should be particularly cautious when considering the use of St. John's Wort with coffee, as they may be more susceptible to the adverse effects of these interactions.

Always consult with a healthcare provider before combining any supplement with medications or common substances like caffeine, as individual reactions can vary based on dosage, overall health, and other medications being taken. This consultation is crucial for ensuring safe use and minimizing the risk of adverse effects.

From the Research

Safety of Mixing St. John's Wort with Coffee

There is no direct evidence in the provided studies regarding the safety of mixing St. John's Wort with coffee. However, we can look at the general interactions of St. John's Wort with other substances:

  • St. John's Wort is known to interact with various drugs by inducing cytochrome P450 enzymes, particularly CYP 3A4, and P-glycoprotein 2, 3, 4, 5.
  • These interactions can lead to decreased plasma concentrations of certain drugs, such as cyclosporine, digoxin, and oral contraceptives 2, 3, 5.
  • St. John's Wort can also cause serotonin syndrome when combined with serotonin reuptake inhibitors 2, 3, 6, 5.
  • The herb has been shown to have an encouraging safety profile as a monotherapy, but its potential for drug interactions is high 2, 3, 4.

Considerations for Caffeine Interaction

While there is no specific information on the interaction between St. John's Wort and coffee, caffeine is a substance that can interact with various medications:

  • Caffeine is metabolized by the liver and can be affected by enzymes such as CYP 1A2 and CYP 3A4.
  • However, without direct evidence, it is unclear whether St. John's Wort's induction of CYP 3A4 would significantly affect caffeine metabolism.

Precautions and Recommendations

Given the potential for St. John's Wort to interact with various substances, it is essential to exercise caution when combining it with any medication or herbal supplement:

  • Individuals taking St. John's Wort should inform their healthcare provider about all medications, including over-the-counter drugs and herbal supplements 6.
  • Healthcare providers should monitor patients for potential interactions and adjust treatment plans accordingly 5.

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

Drug interactions with St. John's Wort (Hypericum perforatum): a review of the clinical evidence.

International journal of clinical pharmacology and therapeutics, 2004

Research

About the cover: St. John's wort.

Journal of the Society for Integrative Oncology, 2006

Research

Pharmacokinetic interactions of drugs with St John's wort.

Journal of psychopharmacology (Oxford, England), 2004

Research

Herb-drug interactions.

Lancet (London, England), 2000

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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