Can I take Glucosamine and St john's wort together?
Drug interaction guide
Originally published 25 Jan 2026
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There are no known significant interactions between glucosamine and St John's Wort. It is generally considered safe to take these two supplements together.
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Why this happens
Glucosamine is primarily used by the body to build cartilage and does not significantly affect the liver enzymes (Cytochrome P450) that St John's Wort is known to influence. St John's Wort works by altering brain chemicals and speeding up the breakdown of certain medicines in the liver, but it does not interfere with how the body processes glucosamine.
What you should do
You can take these supplements together. However, always inform your doctor or pharmacist about all supplements you are taking, especially as St John's Wort can interact with many prescription medicines (such as blood thinners, antidepressants, and the contraceptive pill).
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Using other medicines
Taking multiple medicines? Our Medicines Interaction Checker helps you check whether your prescriptions, over-the-counter medicines, and supplements are safe to take together. Simply search for your medicines to see potential interactions and what to do about them.
Disclaimer
This information is for general educational purposes only and should not be relied upon as a substitute for professional medical advice. Always consult your GP, pharmacist, or another qualified healthcare professional before making decisions about your medications. Individual circumstances may vary, and only a healthcare professional who knows your medical history can provide personalised guidance.
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Article history
The information on this page is written and peer reviewed by qualified clinicians.
25 Jan 2026 | Originally published

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