Herbal Products and Supplements: What You Should Know

This information was developed as part of an educational program made possible by an unrestricted educational grant from McNeil Consumer & Specialty Pharmaceuticals.

Are herbal health products and supplements safe because they’re natural?

Not necessarily. Don’t think that herbal health products and supplements are safer than medicines just because they occur in nature or come from plants. After all, many plants are poisonous! Although herbal products and supplements are advertised as “natural,” they aren’t necessarily natural to the human body.

Unlike prescription and over-the-counter (OTC) medicines, herbal products and supplements don’t have to be tested to prove they work well and are safe before they’re sold. Also, they may not be pure. They might contain other ingredients, such as plant pollen, that could make you sick. Sometimes they contain drugs that aren’t listed on the label, such as steroids or estrogens. Some of these products may even contain toxic (poisonous) substances, such as arsenic, mercury, lead and pesticides.

What types of herbal products and supplements are available?

Hundreds of herbal products and supplements are available. They are advertised to treat just about any symptom. However, trustworthy evidence usually doesn’t exist to support these advertising claims.

Some of the most popular herbal products and supplements include chondroitin sulfate, echinacea, ephedra (also called ma huang), garlic, ginkgo biloba, ginseng, glucosamine, kava, melatonin, phytoestrogens (such as black cohosh, dong quai and soy), saw palmetto and St. John’s wort.

Do any health problems increase the danger of taking herbal products and supplements?

Yes. Herbal products and supplements may not be safe if you have certain health problems. You also may be at increased risk of problems from these products if you are elderly. Talk to your doctor before taking herbal products if you have any of the following health problems:

• Blood clotting problems
• Cancer
• Diabetes
• An enlarged prostate gland
• Epilepsy
• Glaucoma
• Heart disease
• High blood pressure
• Immune system problems
• Psychiatric problems
• Parkinson’s disease
• Liver problems
• Stroke
• Thyroid problems

If you are going to have surgery, be sure to tell your doctor if you use herbal products. Herbal products can cause problems with surgery, including bleeding and problems with anesthesia. Stop using herbal products at least 2 weeks before surgery, or sooner if your doctor recommends it.