Can I take Black cohosh and St john's wort together?

Why this happens

Both supplements are processed by the liver. St John's wort is a potent inducer of liver enzymes (specifically CYP3A4), which can speed up the breakdown of other substances. Furthermore, both herbs have been independently linked to rare cases of hepatotoxicity (liver damage), and taking them together may theoretically increase this risk.

What you should do

You should consult your doctor or a pharmacist before taking these two supplements together. If you do use them, watch for signs of liver trouble, such as yellowing of the eyes or skin (jaundice), dark urine, severe stomach pain, or unusual tiredness. It is also important to tell your doctor if you are taking any other prescribed medications, as St John's wort interacts with many common drugs.

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.