Gymnema (Gymnema Sylvestre R. Br.)
  
Gymnema (Gymnema Sylvestre R. Br.)
Background
Preliminary human evidence suggests that gymnema may be effective in the management of blood sugar levels in type 1 and type 2 diabetes, as an adjunct to conventional drug therapy, for up to 20 months. Gymnema appears to lower serum glucose and glycosylated hemoglobin (HbA1c) levels following chronic use, but may not have significant acute effects. High-quality human trials are lacking in this area. There is early evidence suggesting possible efficacy of gymnema as a cholesterol-lowering agent.
Some of the available research has been conducted by authors affiliated with manufacturers of gymnema products.
Synonyms
Asclepias geminata roxb., Asclepiadaceae , Gemnema melicida , GS4 (water soluble extract of the leaves), Gur-Mar, Gurmar, Gurmarbooti, Gymnema inodum , Kogilam, Mangala gymnema, Merasingi, Meshashingi, Meshavalli, Periploca of the Woods, Periploca sylvestris, Podapatri, Proβeta®, ram's horn, small Indian ipecac, Sarkaraikolli, Sirukurinja.
Evidence
These uses have been tested in humans or animals. Safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider.
Uses based on scientific evidenceGrade*Diabetes
Animal studies report that gymnema can lower blood sugar levels. Preliminary human research reports that gymnema may be beneficial in patients with type 1 or type 2 diabetes when it is added to diabetes drugs being taken by mouth or to insulin. Further studies of dosing, safety, and effectiveness are needed before a strong recommendation can be made.
B
High cholesterol
Reductions in levels of serum triglycerides, total cholesterol, and low-density lipoprotein ("bad cholesterol") have been observed in animal studies. Preliminary research in people with type 2 diabetes reports decreased cholesterol and triglyceride levels. Better evidence is needed before a clear conclusion can be drawn.
C
* Key to grades
A: Strong scientific evidence for this use;
B: Good scientific evidence for this use;
C: Unclear scientific evidence for this use;
D: Fair scientific evidence against this use (it may not work);
F: Strong scientific evidence against this use (it likely does not work).
Uses based on tradition or theory
The below uses are based on tradition or scientific theories. They often have not been thoroughly tested in humans, and safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider.
Aphrodisiac, cancer, cardiovascular disease, constipation, cough, digestive stimulant, diuresis, gout, liver protection, high blood pressure, laxative, liver disease, malaria, obesity, rheumatoid arthritis, snake venom antidote, stomach ailments, uterine stimulant.
Dosing
The below doses are based on scientific research, publications, traditional use, or expert opinion. Many herbs and supplements have not been thoroughly tested, and safety and effectiveness may not be proven. Brands may be made differently, with variable ingredients, even within the same brand. The below doses may not apply to all products. You should read product labels, and discuss doses with a qualified healthcare provider before starting therapy.
Standardization
Standardization involves measuring the amount of certain chemicals in products to try to make different preparations similar to each other. It is not always known if the chemicals being measured are the "active" ingredients. At least one manufacturer offers an extract of gymnema standardized to 25% gymnemic acid, but this extract has not been thoroughly studied.
An extract from gymnema, labeled GS4, has been used in human research. GS4 has since been patented as the product Proβeta®. According to the makers of Proβeta®, the preparation is standardized to a specific biological result, as measured by a test developed by the company, which evaluates "pancreotropic®" effects.
Adults (18 years and older)
Type 1 diabetes : 200 milligrams of extract GS4 taken by mouth, twice daily, under careful continuation of insulin has been studied.
Type 2 diabetes : 200 milligrams of extract GS4 taken by mouth, twice daily, or 2 milliliters of an aqueous decoction (10 grams of shade-dried powdered leaves per 100 milliliters), three times daily has been studied.
Note : The manufacturer PharmaTerra recommends the dose for their product Proβeta® (GS4) to be two 250 milligram capsules taken twice daily at mealtimes (for adults weighing more than 100 pounds), or one 250 milligram capsule taken twice daily at mealtimes (for adults weighing less than 100 pounds).
Children (younger than 18 years)
There is not enough scientific evidence to safely recommend gymnema for use in children.
Safety
The U.S. Food and Drug Administration does not strictly regulate herbs and supplements. There is no guarantee of strength, purity or safety of products, and effects may vary. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy. Consult a healthcare provider immediately if you experience side effects.
Allergies
Allergy to gymnema may occur. In theory, allergic cross-reactivity may exist with members of the Asclepiadaceae (milkweed) family.
Side Effects and Warnings
Aside from lowered blood sugar and increased effects of anti-diabetic drugs following chronic use of gymnema, no significant adverse effects have been reported with the herb, in several studies up to 20 months long. Caution is advised in patients with diabetes or low blood sugar, and in those taking drugs, herbs, or supplements that affect blood sugar. Serum glucose levels may need to be monitored by a qualified healthcare provider, and medication adjustments may be necessary. Based on human and animal studies, gymnema may lower blood cholesterol levels.
Gymnema is reported to suppress the ability to detect sweet tastes, due to the component gurmarin. This phenomenon prompted the Hindi name gurmar or "sugar destroyer."
Pregnancy and Breastfeeding
Gymnema should not be used during pregnancy or breastfeeding due to lack of reliable safety information.
References
1. Ananthan R, Baskar C, NarmathaBai V, et al. Antidiabetic effect of Gymnema montanum leaves: effect on lipid peroxidation induced oxidative stress in experimental diabetes. Pharmacol Res 2003;48(6):551-556.
2. Ananthan R, Latha M, Pari L, et al. Effect of Gymnema montanum on blood glucose, plasma insulin, and carbohydrate metabolic enzymes in alloxan-induced diabetic rats. J Med Food 2003;6(1):43-49.
3. Baskaran K, Ahamath B, Shanmugasundaram K, et al. Antidiabetic effect of a leaf extract from Gymnema sylvestre in non-insulin-dependent diabetes mellitus patients. J Ethnopharm 1990;30:295-305.
4. Chattopadhyay RR. Possible mechanism of antihyperglycemic effect of Gymnema sylvestre leaf extract, Part I. Gen Pharm 1998;31(3):495-496.
5. Gholap S, Kar A. Effects of Inula racemosa root and Gymnema sylvestre leaf extracts in the regulation of corticosteroid induced diabetes mellitus: involvement of thyroid hormones. Pharmazie 2003;58(6):413-415.
6. Jiang H. [Advances in the study on hypoglycemic constituents of Gymnema sylvestre (Retz.) Schult]. Zhong Yao Cai 2003;26(4):305-307.
7. Kamei K, Takano R, Miyasaka A, et al. Amino acid sequence of sweet-taste-suppressing peptide (gurmarin) from the leaves of Gymnema sylvestre. J Biochem 1992;111:109-112.
8. Khare AK, Tondon RN, Tewari JP. Hypoglycaemic activity of an indigenous drug (Gymnema sylvestre, "Gurmar") in normal and diabetic persons. Indian J Physiol Pharm 1983;27:257-258.
9. Kothe A, Uppal R. Antidiabetic effects of Gymnema sylvestre in NIDDM - a short study. Indian J Homeopath Med 1997;32 (1-2) :61-62, 66.
10. Murakami N, Murakami T, Kadoya M, et al. New hypoglycemic constituents in "gymnemic acid" from Gymnema sylvestre. Chem Pharm Bull 1996;44(2):469-471.
11. Porchezhian E, Dobriyal RM. An overview on the advances of Gymnema sylvestre: chemistry, pharmacology and patents. Pharmazie 2003;58(1):5-12.
12. Satdive RK, Abhilash P, Fulzele DP. Antimicrobial activity of Gymnema sylvestre leaf extract. Fitoterapia 2003;74(7-8):699-701.
13. Shanmugasundaram ERB, Rajeswari G, Baskaran K, et al. Use of Gymnema sylvestre leaf extract in the control of blood glucose in insulin-dependent diabetes mellitus. J Ethnopharm 1990;30(3):281-294.
14. Shimizu K, et al. Suppression of glucose absorption by extracts from the leaves of Gymnema inodorum. J Vet Med Sci 1997;59:753-757.
15. Xie JT, Wang A, Mehendale S, et al. Anti-diabetic effects of Gymnema yunnanense extract. Pharmacol Res 2003;47(4):323-329.
January 01, 2004 
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