VCVITAMINS/CHART

The Bottom Line

Use caution with St. John's Wort and NAD precursors together: the ingredients or formulations need review, and limited research does not establish the safety of this exact pair.

VERDICT

St. John's Wort and NAD precursors together require more care than a neutral matrix label suggests. St. John's wort has a substantial medicine-interaction burden. The absence of a documented direct interaction with the other supplement does not clear the combination for someone taking prescriptions, and spacing doses does not reverse enzyme induction. The practical decision depends on the formulation, your medicines, and your response.

Use with caution Limited evidence
01 / MECHANISM

How They Interact

St. John's wort can induce drug-metabolizing enzymes and transporters, reducing the exposure to many medicines. NR and NMN are precursors in NAD metabolism; changes in blood biomarkers do not establish longer life or better health. These individual roles do not establish that St. John's Wort improves the absorption or effectiveness of NAD precursors, or vice versa. Direct clinical evidence for this particular combination is limited. St. John's wort has a substantial medicine-interaction burden. The absence of a documented direct interaction with the other supplement does not clear the combination for someone taking prescriptions, and spacing doses does not reverse enzyme induction.

02 / BEST PRACTICES

How To Take Them

Have a pharmacist review all medicines before starting or stopping St. John's wort. Avoid treating an NAD biomarker increase as a reason to keep escalating the dose. There is no validated spacing interval that removes the concerns for this combination; reviewing the products and medicines is more useful than choosing an arbitrary time gap. If you miss a supplemental dose, resume the usual schedule instead of doubling the next dose; follow your prescriber's instructions for prescribed products.

03 / FORM MATTERS

Form & Quality Differences

Hyperforin content varies, so one extract's interaction profile cannot be assumed for another. Nicotinamide riboside and nicotinamide mononucleotide are distinct compounds with different research histories.

05

Practical Tips

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Frequently Asked Questions

Who Should Be Careful St. John's wort has a substantial medicine-interaction burden. The absence of a documented direct interaction with the other supplement does not clear the combination for someone taking prescriptions, and spacing doses does not reverse enzyme induction. St. John's wort has serious interactions with antidepressants, contraceptives, transplant medicines, and many other drugs. Long-term safety, pregnancy safety, and benefits of combining NAD precursors with other supplements remain uncertain.
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Sources & Further Reading

  1. NCCIH NCCIH — St. John's Wort
  2. NCCIH NCCIH — Using Dietary Supplements Wisely

Reviewed by Caroline M. on October 20, 2026 for accuracy against the sources listed above. This page is educational and is not a substitute for professional medical advice.

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The matrix has 86 supplements and 7310 pairwise interactions. Click any cell to see the full breakdown.

Back To The Vitamins Chart All St. John's Wort Interactions All NAD+ Precursors (NMN, NR – Nicotinamide Riboside) Interactions