The short answer
Taking prescription medication does not automatically mean you cannot take Chinese herbs. It depends on the medicines you take, the herbs being considered, their doses and your health history.
At Fingertips, we customize every formula and review it against your medications and supplements before prescribing. We use a drug–herb interaction checklist developed specifically for our practice to support this review. If you are concerned about a combination, bring it up. We will talk through what is known, what remains uncertain and whether herbal treatment is appropriate for you.
Keep taking prescribed medication as directed unless your prescribing clinician tells you otherwise.
How herbs and medicines can interact
Herbs contain active compounds. Some can change how the body absorbs or breaks down a medicine, making its effect stronger or weaker. Others can add to a medicine’s effects, such as increasing bleeding risk.[1]
The evidence varies. Some interactions have been documented in people; others are based on laboratory findings or individual case reports. A possible interaction deserves attention, but it does not mean every formula containing that herb will cause harm. Equally, a combination that has not been studied cannot be assumed safe.[3]
Why blood thinners need particular care
Warfarin is sensitive to changes in medicines, supplements and diet. A systematic review identified reports of interactions involving 78 herbs, foods and supplements, with effects in both directions: some increased warfarin’s effect and others reduced it. Reports included goji products and other herbs used in Chinese medicine, although the strength of evidence differed between products.[2]
If you take warfarin, any proposed herbal treatment needs review with your prescribing clinician or anticoagulation service. They may recommend additional INR blood tests when herbs are started, stopped or changed.[5] Other blood thinners also need an individual interaction review; INR testing is used for warfarin, not as a general test for all blood thinners.
Our drug–herb interaction checklist
Questions about combining herbs and medication deserve more than a general reassurance. That is why we developed a drug–herb interaction checklist for Fingertips.
The checklist supports a structured review of your medication list alongside the proposed formula. We consider known and potential interactions, the available evidence and your individual health needs. We then explain any concerns and how they affect the treatment recommendation.
Every formula is customized, including the ingredients, proportions and dose. Where appropriate, we can change the formula or leave out an unsuitable herb. Some combinations require your doctor’s or pharmacist’s input, and sometimes we recommend holding off on herbs.
The checklist is a practical reference within that process. Research does not cover every combination, so follow-up and communication with your other clinicians remain part of your care.[3]
What to bring to your consultation
Please bring a current list, or clear photos of the labels, showing:
- Prescription medicines, including the dose and how often you take them.
- Over-the-counter medicines, including occasional painkillers, allergy medicines and sleep aids.
- Vitamins, supplements and other herbal products, including herbal teas or extracts you use regularly.
Let us know why you take each medicine, any allergies or past reactions, and whether anything has recently changed. Relevant blood tests and medical records are helpful too.
Keeping your care coordinated
Tell your doctor and pharmacist about your herbal treatment, and share the formula’s ingredient list. Let us know whenever a medicine or supplement is started, stopped or changed so we can review the combination again.
Some situations need closer coordination before herbs are prescribed, particularly treatment with warfarin, transplant medicines, digoxin or cancer medicines, where a change in drug effect can have serious consequences.[3] Please also tell us about liver or kidney disease, pregnancy, breastfeeding, or a planned procedure so these can be considered in your assessment.
Before surgery, give your surgical and anesthesia teams a full list of herbs and supplements. Some affect bleeding or anesthesia, and the team may ask you to stop them in advance. Follow their instructions about when to stop and restart.[4]
If you take a blood thinner and develop unusual bleeding or bruising, contact your medical team promptly. Bleeding that is heavy or will not stop needs emergency care.[5]
How we approach herbal medicine at Fingertips
We begin with your concerns, your goals and the care you already receive. Your medication list is part of that conversation from the start.
Our aim is to find a treatment that makes sense for you. That means a customized formula when appropriate, a clear explanation of the interaction review, and adjustments as your health or medicines change.
Read more about how herbal formulas are kept safe and acupuncture while taking blood thinners.
Common questions
Can I take Chinese herbs with warfarin?+
Do not start herbs without review by your prescribing clinician or anticoagulation service. Some herbs can increase or reduce warfarin’s effect. If treatment is considered appropriate, your medical team may arrange extra INR checks when herbs are started, stopped or changed.[2][5]
Can I take herbs with antidepressants?+
It depends on the antidepressant and the herbs. St John’s wort, for example, has documented interactions with several antidepressants.[1] That does not mean all Chinese herbal formulas have the same risk. Bring the exact medicine name and dose so we can review the proposed formula and involve your prescriber or pharmacist when needed.
Does taking herbs a few hours apart from medication prevent interactions?+
Spacing them apart may help with some absorption-related interactions, but it does not prevent all interactions. Effects on drug breakdown or blood clotting can last beyond the time you take a dose.[1] Follow advice specific to your medicines and formula rather than relying on a fixed time gap.
Should I stop herbs before surgery?+
Your surgical or anesthesia team may ask you to stop them, sometimes at least two weeks beforehand. Tell them what you take as early as possible and follow their instructions for your procedure.[4]
Do I need to tell my doctor I take herbs?+
Yes. Share the ingredient list with your doctor and pharmacist, and tell us about any changes to your medication. Having the same information helps everyone involved in your care make better decisions.
References
- Izzo, A. A., & Ernst, E. (2009). Interactions between herbal medicines and prescribed drugs: An updated systematic review. Drugs, 69(13), 1777–1798. https://doi.org/10.2165/11317010-000000000-00000
- Tan, C. S. S., & Lee, S. W. H. (2021). Warfarin and food, herbal or dietary supplement interactions: A systematic review. British Journal of Clinical Pharmacology, 87(2), 352–374. https://doi.org/10.1111/bcp.14404
- National Center for Complementary and Integrative Health. (2024). Herb-drug interactions. https://www.nccih.nih.gov/health/providers/digest/herb-drug-interactions
- American Society of Anesthesiologists. (2020). Herbal and dietary supplements and anesthesia. https://madeforthismoment.asahq.org/wp-content/uploads/2020/10/ASA_Supplements-Anesthesia_Updated-1.pdf
- University Hospital Southampton NHS Foundation Trust. (2023). Warfarin: Patient information factsheet. https://www.uhs.nhs.uk/Media/UHS-website-2019/Patientinformation/Medicinestherapiesandanaesthetics/Warfarin-2306-PIL.pdf