What the NHS says about mixing herbal products with medicines, who needs extra care, and the questions to ask your pharmacist before you start a supplement.
Quick answer: Not always. The NHS says some medicines do not mix well with herbal medicines, and it advises checking with a pharmacist before taking a herbal medicine if you already take other medicines, including ones you buy without a prescription. Never stop a prescribed medicine in order to take a supplement.
Last updated: 12 October 2026
At a glance
- Check first: with a pharmacist, GP or nurse before starting
- Take extra care: if you use blood thinners, are having surgery, are pregnant or have a medical condition
- Never: stop a prescribed medicine or double up on herbal ingredients
- Bring: the product and its full ingredient list
Why natural does not mean interaction-free
Herbal products are made from plants, so many people assume they are harmless. A Wirral University Teaching Hospital NHS leaflet makes the point clearly: herbal medicines have an effect on the body and can lead to side effects, so they should be used with care. They may interact with other medicines, with medical conditions, or be unsafe around surgery. It says to let your doctor, nurse or pharmacist know about any herbal medicines you take.
What the NHS says
The NHS page on herbal medicines and complementary therapies states that not all herbal medicines are safe or suitable for everybody. In summary:
- Herbal medicines are not recommended for children.
- Some medicines do not mix well with herbal medicines, which may cause harmful effects or stop your medicine working.
- You can check the leaflet in your medicine packet, and you should always check with a pharmacist before taking a herbal medicine if you take other medicines, including ones you can get without a prescription.
- You should be especially careful if you take blood thinning medicines or are at increased risk of bleeding or stroke.
- Do not buy unlicensed herbal medicines online, as they may not be safe.
Who needs extra care
The NHS Specialist Pharmacy Service guidance on herbal and conventional medicines says that people taking medicines with a narrow margin between a helpful and a harmful dose, such as warfarin, should avoid herbal medicines, and that herbal medicines should never be used in place of conventional ones. It also advises looking out for people taking several combination products, because the same herbal ingredient can be repeated and dosed excessively. People with higher-risk medical conditions should also avoid herbal medicines unless advised otherwise.
Five questions to ask your pharmacist
- Is this herbal ingredient known to interact with any of my medicines?
- Is it suitable with my medical conditions?
- Is it safe if I am pregnant, breastfeeding or planning surgery?
- Is there a maximum amount or time limit?
- Which side effects mean I should stop and call you?
How to make the conversation easy
- Bring the pack, or a photo of the label with the full ingredient list.
- Keep a simple list of everything you take, including vitamins, teas and supplements.
- Tell the team looking after you before an operation or procedure.
- Do not stop a prescribed medicine without medical advice.
Where GenieHeal fits
Every GenieHeal product page lists the full ingredients and safety information, and we ask anyone who takes medication, is pregnant or breastfeeding, or has a medical condition to speak to a doctor or pharmacist first. For one example of why, see our guide to aloe and cascara sagrada in herbal supplements, and our checklist for choosing a herbal supplement. If you have a question about a product, contact our team.
Frequently asked questions
Can I take herbal supplements with prescription medicines?
Check with a pharmacist first. The NHS says some medicines do not mix well with herbal medicines, and this includes medicines you can buy without a prescription.
Who should avoid herbal supplements?
Children, people taking some medicines such as blood thinners, and people with higher-risk medical conditions should avoid them unless a professional advises otherwise. If you are pregnant or breastfeeding, ask first.
Do I need to tell my surgeon?
Yes. Herbal products can be unsafe around surgery, so tell the team looking after you.
Should I stop my medicine to take a supplement?
No. Never stop a prescribed medicine without medical advice.
Sources
- NHS: Herbal medicines and complementary therapies
- NHS Specialist Pharmacy Service: herbal medicines and interactions
- Wirral University Teaching Hospital NHS Foundation Trust: I take herbal medicines, should I mention it?
Keep reading
- Aloe and cascara sagrada in herbal supplements
- What is a herbal digestive supplement?
- How to choose a herbal colon cleanse supplement
Browse all GenieHeal herbal food supplements, learn about GenieHeal, or contact our team.
GenieHeal products are food supplements, not medicines. They are not intended to diagnose, treat, cure or prevent any disease, and they should not replace a varied, balanced diet or medical advice. This article is general information, not medical advice. If you are worried about your health, speak to your GP or pharmacist.
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Questions about a product? Email info@genieheal.com.
