Scientific Name: Gymnema sylvestre
Other Names: Gurmar, Merasingi

Who is this for?

Uses

Although gymnema sylvestre has been used to treat a number of conditions. It is best known for its possible ability to lower blood sugar levels. Results from case reports and studies in humans and animals suggest that it may work in several ways to help control both type 1 diabetes and type 2 diabetes. First, the acids contained in gymnema sylvestre may decrease the amounts of sugar that are absorbed from foods. As a result, blood sugar levels may not increase as much as usual after meals. Secondly, gymnema sylvestre may stimulate the production of insulin by the body. Possibly, it may even prompt the pancreas to develop more beta cells--the source of insulin. It may also make body cells more responsive to the insulin that is available. Finally, several studies have shown that chewing on the leaves of gymnema sylvestre dulls the sense of taste for sweet foods. Because chemicals in gymnema sylvestre are shaped like sugar molecules, they replace some of the sugar molecules on taste buds?interfering with the ability to taste sweet or bitter foods. Participants in studies tended to consume fewer sweet-tasting foods and drinks after using gymnema sylvestre.

In clinical studies of animals with diabetes, gymnema sylvestre also appeared to reduce body weight, total cholesterol, and triglyceride levels. Although the exact reasons are not clear, gymnema sylvestre is believed to block the absorption of dietary fats into the bloodstream. Possibly, more fats are then eliminated instead of being stored. Some individuals taking gymnema sylvestre for diabetes have also seen a reduction in cholesterol and/or weight, but no clinical studies of gymnema sylvestre?s potential cholesterol-lowering or anti-obesity effects have been reported in humans. All the potential uses of gymnema sylvestre need more study before it can be recommended for medical use.

When should I be careful taking it?

Precautions

Because gymnema sylvestre is known to lower levels of blood sugar, individuals who use insulin or take oral medications to control diabetes should use it with caution. If blood sugar levels fall too low, shakiness, sweating, confusion, distorted speech, and loss of muscle control may occur. If it is not corrected, low blood sugar can lead to unconsciousness and even death.

Very little information is available on how gymnema sylvestre might affect a developing fetus, an infant, or a small child. Therefore, its use is not recommended during pregnancy, while breastfeeding, or during early childhood.

What side effects should I watch for?

Although no side effects have been attributed to the use of gymnema sylvestre, its possible lowering effect on blood sugar may potentially result in hypoglycemia (blood sugar that is too low). Signs that blood sugar may be too low include shakiness, sweating, confusion, distorted speech, and loss of muscle control. If not corrected, low blood sugar can lead to unconsciousness and even death.

What interactions should I watch for?

Prescription Drugs

Gymnema sylvestre may increase the blood sugar lowering effects of insulin and oral drugs for diabetes, such as:

  • acarbose
  • Actos
  • Avandia
  • glimepiride
  • glipizide
  • glyburide
  • Glyset
  • metformin
  • Prandin

The cholesterol-lowering effects of drugs such as Crestor, Lipitor, lovastatin, pravastatin, and simvastatin may be increased by taking gymnema sylvestre.

Herbals

Because gymnema sylvestre may decrease blood sugar levels, taking it with other blood sugar-lowering herbal products may result in hypoglycemia--blood sugar that is too low. Herbals that may reduce blood sugar include:

  • Eleuthero
  • Fenugreek
  • Ginger (in high amounts)
  • Kudzu
  • Panax Ginseng

Some interactions between herbal products and medications can be more severe than others. The best way for you to avoid harmful interactions is to tell your doctor and/or pharmacist what medications you are currently taking, including any over-the-counter products, vitamins, and herbals. For specific information on how gymnema sylvestre interacts with drugs, other herbals, and foods and the severity of those interactions, please use our Drug Interactions Checker to check for possible interactions.

Should I take it?

Long used in traditional medicine in India and Pakistan, gymnema sylvestre is rapidly becoming more popular in other areas of the world. Believed to be native to India and northern Africa, it is now grown commercially in southeastern Asia, Australia, Europe, and North America. The plants grow slowly as long vines with sturdy but flexible stems. Closely related to milkweed, wild gymnema sylvestre climbs on trees and other tall vegetation, mostly in shaded areas. On farms, it is cultivated on fences or arbors like grape vines. For medicine, the leaves are collected and dried to be made into capsules or liquid preparations. To diminish the sense of taste for sweet substances--possibly as a form of weight control--fresh gymnema sylvestre leaves are often chewed like gum by residents of areas where it grows naturally.

Dosage and Administration

In human studies, the most common doses of gymnema sylvestre used for blood sugar control were 400 mg to 600 mg per day. Frequently, gymnema sylvestre is added to many different herbal combination products, but the majority of studies used GS4, a standardized product that contains only gymnema sylvestre. Standardization by the manufacturer should assure the same amount of active ingredient in every batch of the commercial preparation. Standardization of herbal products is not required by the U.S. Food and Drug Administration (FDA), so not every product will contain the same amounts of active ingredients.

A tea may be made by adding about one teaspoon of dried gymnema sylvestre leaves to 8 ounces of boiling water. After allowing the leaves to simmer for a few minutes, the solid particles are removed. Often, the tea is taken an hour before meals.


Summary

Historically, gymnema sylvestre has been used to treat conditions ranging from malaria to snake bites. It may be most effective for the treatment of diabetes, however; and results from several studies seem to show that it does have a lowering effect on blood sugar. It may also decrease blood cholesterol levels.

Risks

Due to little information about gymnema sylvestre's possible effects on developing babies, infants, and small children; its use is not recommended for pregnant or breast-feeding women or young children.

Side Effects

Gymnema sylvestre may cause blood sugar levels to become too low, possibly resulting in hypoglycemia.

Interactions

Because gymnema sylvestre may have a lowering effect on blood sugar, taking it may increase the effectiveness of products used for the treatment of diabetes. Individuals who are taking medications or herbals for diabetes should talk to a doctor or pharmacist before using gymnema sylvestre.

Last Revised April 15, 2008

References

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Last Revised: April 15, 2008

Note: The above information is not intended to replace the advice of your physician, pharmacist, or other healthcare professional. It is not meant to indicate that the use of the product is safe, appropriate, or effective for you.

In general, herbal products are not subject to review or approval by the U.S. Food and Drug Administration (FDA). They are not required to be standardized, meaning that the amounts of active ingredients or contaminants they contain may vary between brands or between different batches of the same brand. Not all of the risks, side effects, or interactions associated with the use of herbal products are known because few reliable studies of their use in humans have been done.

This information is provided for your education only. Please share this information with your healthcare provider and be sure that you talk to your doctor and pharmacist about all the prescription and non-prescription medicines you take before you begin to use any herbal product.

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