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What to Know About Herbs and Surgery

Millions of people in the U.S. use an herbal supplement for health benefits. It could be Echinacea to prevent a cold or ginkgo to improve memory. On the surface, using these products sounds like a good idea. They are considered “natural” and are sold in pharmacies and health stores. You might think that they must be safe.

But, natural doesn’t always mean safe. The FDA doesn’t control herbal supplements the same way it does prescription and over-the-counter (OTC) medicines. The standards of safety are not the same. That could be a problem for you, especially if you need to have surgery.

Many health organizations advise that all herbal supplements be stopped 2 to 3 weeks before surgery. This includes the American Society of Anesthesiologists. They advise you stop the supplements because these herbs can have side effects that could make surgery more dangerous for you.

Herbs as medicine

The use of plants as medicines goes back to ancient times. The Egyptians believed aloe vera prolonged life. The Bushmen of the Kalahari in Africa have used the flowering cactus, hoodia, for centuries to ward off hunger. In India and China, herbal medicines are important parts of medical practice.

Many of the medicines we depend on every day are based on plants. This includes digitalis, aspirin, morphine, and even some cancer medicines. But when you take an herbal supplement that has not been controlled for safety by the FDA, you don't know what you are getting.

Herbs can have unexpected side effects. And not all the active ingredients may be known. Most of these products have not been studied in large, controlled research trials. Their safety, side effects, and how well they work aren’t certain. Also, the manufacturing process isn't well-regulated. Because of this, some supplements may have ingredients that are not on the label. 

The problem with herbs and surgery

Taking herbs in the weeks before surgery could cause a bad reaction with anesthesia medicines. Or they may cause too much bleeding during and after surgery. This is dangerous because many people taking herbal supplements don't tell their surgeon or anesthesiologist about them.

These eight common herbal supplements could be a problem if you need to have surgery:

  • Echinacea. This herb comes from the purple cornflower and is taken for colds, infections, arthritis, and ulcers. If you have liver disease and you have anesthesia while taking Echinacea, you could end up with liver damage.

  • Ephedra. Also called ma-huang, this herb from the plant Ephedra sinica is used for asthma and to suppress appetite. When combined with some anesthesia medicines, it can cause high blood pressure and abnormal heart rhythms. The FDA banned it in 2003 after being linked to several deaths.

  • Garlic. Garlic supplements are used to lower blood pressure and cholesterol. Garlic can increase the effects of medicines used to control blood sugar, blood thinners, and some OTC pain relievers. It can also increase bleeding during or after surgery.

  • Ginkgo. This is used to improve memory. But it may cause prolonged bleeding during or after surgery.

  • Ginseng. This is commonly used for an energy boost or to lower blood sugar levels. During surgery, ginseng may cause high blood pressure and a rapid heart rate.

  • Kava. This supplement is used for muscle relaxation and to calm the nerves. It may be dangerous for people having surgery because of its interactions with other medicines. It may increase the effects of anesthesia and also cause liver damage.

  • St. John's wort. Also known as goat weed, this herb is taken to relieve depression and anxiety. During a surgical procedure, St. John's wort may interfere with some anesthesia medicines and make it harder for you to recover from the effects of anesthesia. It can also affect your blood pressure.

  • Valerian. This herb is used to relieve anxiety. It may increase the effects of anesthesia and make it harder to wake up after surgery. It may also cause irregular heart rhythms.

Other herbs that may increase bleeding include:

  • Feverfew

  • Ginger

  • Saw palmetto

Herbs that could change your blood pressure during surgery include:

  • Goldenseed

  • Licorice

  • Milk thistle

Remember that herbal supplements are not FDA-approved medicines. They may have many benefits. But they aren't as reliable and safe as prescription and OTC medicines.

The best advice is to talk with your healthcare provider about all OTC medicines and herbal supplements you’re taking. If you have any surgery planned, have this talk right away. Also, plan to stop these herbs in the weeks before your surgery. 

Online Medical Reviewer: Mahammad Juber MD
Online Medical Reviewer: Marianne Fraser MSN RN
Online Medical Reviewer: Raymond Turley Jr PA-C
Date Last Reviewed: 9/1/2023
© 2000-2024 The StayWell Company, LLC. All rights reserved. This information is not intended as a substitute for professional medical care. Always follow your healthcare professional's instructions.