Should You Stop Supplements Before Surgery?

Written by Lize Bührmann, founder of Pharmatropia.

Do not decide on your own which supplements to continue before surgery. Give the surgeon, anaesthetist and pre-operative team a complete list of everything you take. Many clinical services advise stopping non-essential herbal products and dietary supplements about two weeks before planned surgery, but the correct timing varies by product, procedure and medical need. Prescribed medicines and clinician-directed supplements must not be stopped without instructions.

Why supplements matter before an operation

Some supplements may affect:

• bleeding or clotting;
• blood pressure, heart rate or blood sugar;
• sedation and the response to anaesthetic medicines;
• liver enzymes that process medicines;
• electrolytes or fluid balance;
• recovery and medicines used after surgery.

“Natural” does not mean invisible to anaesthesia. Multi-ingredient sleep, stress, energy and circulation products can be especially difficult to assess because several ingredients may point in the same direction.

How long before surgery should supplements be stopped?

A two-week pause is common general guidance for non-essential complementary products, including in NHS and NCCIH resources. It is not a universal rule. Some products may require a different interval, and some nutrients may be continued for a specific medical reason.

Your procedure’s instructions take priority. Ask early enough for the team to assess the list rather than stopping everything the night before.

What to take to the pre-operative assessment

1. Bring the original bottles or clear photographs of the front and back labels.
2. Record the product name, full ingredients, serving, frequency and last dose.
3. Include teas, tinctures, powders, gummies, patches, oils, traditional medicines and recreational substances.
4. List prescription and over-the-counter medicines separately.
5. Ask for a written continue/stop/restart plan.

If you use several blends, our duplicate-ingredient checklist can help you prepare the list. For proprietary formulations, see how to read a proprietary blend.

Supplements often discussed before surgery

Clinical teams commonly ask about products associated with bleeding, sedation, blood pressure or glucose effects. Examples may include garlic concentrates, ginkgo, ginseng, feverfew, valerian, kava, St John’s wort, ashwagandha, CBD products, fish oil and high-dose vitamins or minerals.

This is not a self-treatment list and does not mean every product has the same level of evidence or risk. Brand formulas and amounts differ. Report everything rather than trying to decide which products “count”.

What if surgery is urgent?

Do not delay emergency care because you recently took a supplement. Tell the emergency and anaesthetic teams what you used, how much and when. Bring the container if practical. That information helps them anticipate interactions and monitor appropriately.

When can supplements be restarted?

Ask before discharge. Surgery may change bleeding risk, eating, kidney or liver function, wound healing, mobility and the medicines you are prescribed. A product that was acceptable before surgery may not suit the immediate recovery period.

Frequently asked questions

Do vitamins need to be stopped too?

Some may be continued and others may need pausing, depending on dose and purpose. Include every vitamin on the list and follow the surgical team’s instructions.

What about homeopathic products?

Highly diluted products differ from herbal extracts, but labels may contain alcohol, sugars or additional active ingredients. Disclose them so the team can assess the actual product.

Should I stop magnesium before surgery?

Do not make the decision from a generic article. The answer depends on the form, amount, kidney function, reason for use and procedure.

Can I hide a supplement because the doctor may disapprove?

No. The purpose of disclosure is safe anaesthesia and surgery, not judgement. An incomplete list can remove information the team needs.

Sources and educational note

See NCCIH guidance on supplements and surgery, the American Society of Anesthesiologists’ supplements and anaesthesia brochure, and NHS pre-operative guidance. This article is general education and not an individual stop/start plan.