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Cranberry Extract Side Effects & Safety

This content is for informational purposes only and does not constitute medical advice. Consult your healthcare provider before starting any supplement. Full disclaimer

Safety Profile

Overall safety rating: Generally Safe

Potential Side Effects

  • Mild GI symptoms — stomach upset, diarrhea (especially with juice)
  • May increase urinary oxalate — concern for kidney stone formers (cranberry juice more than extracts)
  • Sugar intake — sweetened cranberry juice products can be high in added sugar; use unsweetened or extract

Drug & Supplement Interactions

  • Warfarin — cranberry may increase INR through CYP2C9 inhibition; monitor closely if on warfarin
  • Kidney stones — cranberry may increase oxalate excretion; avoid high doses if prone to calcium oxalate stones
  • Acid-sensitive medications — cranberry may alter urinary pH slightly

Maximum Dose

Do not exceed: No established upper limit; doses up to 144mg PACs daily have been studied safely

Full Cranberry Extract Guide

References

  1. (). Cranberries for preventing urinary tract infections. Cochrane Database of Systematic Reviews. DOI
  2. (). A-type cranberry proanthocyanidins and uropathogenic bacterial anti-adhesion activity. Phytochemistry. DOI