Herbs Before and After Surgery: Bleeding, Anesthesia and Healing
Which herbs sources link to bleeding or anesthesia effects, the stop-before-surgery timing that NCCIH and Memorial Sloan Kettering state, and why the surgical team must know everything you use.
Content last updated . This page has not been medically reviewed.
Safety first. Supplements can cause side effects and interact with medicines. Read mushroom safety and interactions before you use any mushroom product.
Tell your surgeon, anesthesia team and pharmacist about every herb, tea and supplement you use, well before the procedure. NCCIH says that if you are going to have surgery, certain dietary supplements may increase the risk of bleeding or affect your response to anesthesia. [1] NCCIH advises talking to your providers as far in advance of the operation as possible and telling them about all dietary supplements you take. [1] Do not stop a prescribed medicine on your own; ask the prescriber or pharmacist.
Two concerns: bleeding and anesthesia
- Bleeding. Some herbs are described as slowing blood clotting or affecting platelets, the blood cells that help clots form.
- Anesthesia. Some herbs are described as possibly interacting with anesthesia drugs or with sedating medicines used around surgery.
The sources below mostly rest on lab findings, case reports and expert reviews rather than large trials, so the strength of evidence for individual herbs is generally limited. This page labels each statement by who said it.
What named sources say, herb by herb
Timing statements are quoted from the source named and are not personal instructions; the surgical team decides what applies to you.| Herb (plant, form) | What the source says | Source type |
|---|---|---|
| Garlic, Allium sativum (supplements) | NCCIH says garlic supplements may increase the risk of bleeding, which is especially important before surgery or with anticoagulants or aspirin. [2] Memorial Sloan Kettering says garlic supplements should be discontinued 1 to 2 weeks before surgery because of the potential for increased bleeding. [3] | NCCIH; hospital database |
| Ginkgo, Ginkgo biloba | NCCIH says ginkgo may increase bleeding risk in people taking anticoagulants such as warfarin. [4] Memorial Sloan Kettering says it may increase the risk of bleeding. [5] | NCCIH; hospital database |
| Ginger, Zingiber officinale (supplements) | Memorial Sloan Kettering says that because of blood-thinning effects, ginger supplements should be stopped 2 weeks before surgery. [6] | Hospital database |
| Asian ginseng, Panax ginseng | NCCIH says it may interfere with blood clotting. [7] See Asian ginseng. | NCCIH |
| Feverfew, Tanacetum parthenium | NCCIH says it may slow blood clotting and should be stopped at least 2 weeks before scheduled surgery. [8] | NCCIH |
| Turmeric, Curcuma longa | Memorial Sloan Kettering says turmeric may increase your risk of bleeding. [9] | Hospital database |
| Passionflower, Passiflora incarnata | NCCIH says it might interact with some anesthesia drugs, so avoid its use before surgery unless recommended by a provider, and talk to your provider if you take it within 2 weeks of scheduled surgery. [10] | NCCIH |
| Valerian, Valeriana officinalis | Memorial Sloan Kettering says valerian should be stopped at least 1 week before surgery because it can interfere with general anesthesia. [11] | Hospital database |
| Kava, Piper methysticum | Memorial Sloan Kettering says to discontinue kava before surgery as it may interact with anesthetics. [12] | Hospital database |
Different sources give different timing for the same herb (garlic is described as 7 days to 2 weeks), so a single "safe cutoff" cannot be stated from these sources. [3] Timing depends on the herb, the product, the procedure and the person, and the anesthesia team decides.
What this page does not cover
- Herbs not in the table. Absence from the table does not mean an herb is safe before surgery. Lack of evidence is not proof of safety.
- Healing after surgery. "Proper evidence not found": the NCCIH and Memorial Sloan Kettering pages read for this page contain no statement that an herb speeds recovery after an operation. One source, Memorial Sloan Kettering, says ginger supplements should not be used immediately after surgery to control nausea or vomiting. [6]
Practical steps that sources support
- Make a list of every product you use, with the plant name and part on the label, and give it to the surgical team. [1]
- Ask the pharmacist or clinician which products matter for your procedure and what the timing should be for you. A pharmacist can check each product: see how to check interactions.
- If you take an anticoagulant or aspirin, mention it alongside the herbs. NCCIH names these medicines when warning about garlic and ginkgo. [2][4]
More detail on this site
Supplements before surgery covers vitamins and other supplements; Herbs and blood thinners covers warfarin and similar medicines; Herb safety essentials gives the wider picture. Ashwagandha has its own page, Ashwagandha before surgery.Frequently asked questions
How long before surgery should I stop herbal supplements?
There is no single answer in the sources read. NCCIH says feverfew should be stopped at least 2 weeks before scheduled surgery. [8] Memorial Sloan Kettering gives 1 to 2 weeks for garlic, 2 weeks for ginger and at least 1 week for valerian. [3][6][11] Ask the surgical team about your own products.
Why do surgeons ask about herbs?
NCCIH says some supplements may increase the risk of bleeding or affect the response to anesthesia. [1]
Do I need to mention teas and foods?
The sources above concern supplements. For teas or foods used in unusual amounts, the sources read do not say; mention them anyway so the team can decide.
Does garlic in cooking matter?
NCCIH's bleeding warning is about garlic supplements, not food amounts. [2] Mention heavy use to the team if you are unsure.
Can herbs help me recover faster after surgery?
"Proper evidence not found" in the NCCIH and Memorial Sloan Kettering pages searched. Ask the surgical team before using any herb during recovery.
References
- NCCIH (US), Using Dietary Supplements Wisely. Read 2026-10-23.
- NCCIH (US), Garlic. Read 2026-10-23.
- Memorial Sloan Kettering Cancer Center, Garlic (About Herbs). Read 2026-10-23.
- NCCIH (US), Ginkgo. Read 2026-10-23.
- Memorial Sloan Kettering Cancer Center, Ginkgo (About Herbs). Read 2026-10-23.
- Memorial Sloan Kettering Cancer Center, Ginger (About Herbs). Read 2026-10-23.
- NCCIH (US), Asian Ginseng. Read 2026-10-23.
- NCCIH (US), Feverfew. Read 2026-10-23.
- Memorial Sloan Kettering Cancer Center, Turmeric (About Herbs). Read 2026-10-23.
- NCCIH (US), Passionflower. Read 2026-10-23.
- Memorial Sloan Kettering Cancer Center, Valerian (About Herbs). Read 2026-10-23.
- Memorial Sloan Kettering Cancer Center, Kava (About Herbs). Read 2026-10-23.