Can You Take Calcium and St. John's Wort Together?

No documented interaction was identified between calcium and St. John's Wort in the sources reviewed.

No documented interaction identifiedEvidence: Moderate

See the full Calcium page and St. John's Wort page for other reviewed interactions and reference information.

What the interaction means

NCCIH's St. John's Wort page names several drugs it can weaken (antidepressants, birth control, cyclosporine, anticonvulsants, heart medications, HIV drugs, cancer medications, warfarin, certain statins) -- calcium is not among them. Calcium's own NIH ODS fact sheet names dolutegravir, levothyroxine, lithium, and quinolone antibiotics as its documented drug interactions -- St. John's Wort is not among them either.

No documented interaction between Calcium and St. John's Wort was identified in the authoritative sources reviewed. This is not a guarantee that no interaction exists for every dose, formulation, or individual -- it means the sources checked did not document one.

Practical context

NCCIH's St. John's Wort page and calcium's NIH ODS fact sheet were checked directly, full text, in both directions. Neither source names the other.

What the sources say

Last reviewed 2026-08-25

Medical information disclaimer: this information is general and educational. It does not diagnose conditions, prescribe treatment, or determine whether a combination is safe for you personally. Follow your prescription label and ask a pharmacist or clinician before starting, stopping, or combining products. Full disclaimer.

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