The purpose of this study is to examine whether the ingestion of the herbal dietary supplement Ginkgo biloba extract has any effect on the efficacy of three classes of diabetic medications - (Glucotrol, Glucophage and Actose). Additionally, the study will examine the effect of Ginkgo biloba extract on pancreatic insulin production in non-diabetic subjects between the ages of 20 and 75 years old.

Herbal remedy is popular among those with chronic diseases, who may already be taking several prescription medications, thereby increasing the risk of drug-herb interactions. Ginkgo biloba extract is a popular dietary supplement that is ingested by the general population to enhance mental focus and by the elderly to delay onset of age-acquired loss of cognitive function. In subjects with non-insulin dependent diabetes (NIDDM), ingestion of Ginkgo biloba may decrease efficacy of the hypoglycemic agents and increase whole body insulin resistance. Because aging is a significant risk factor for the development of NIDDM as a result of a progressive decline in pancreatic function, and because the elderly chronically take multiple prescription medications, the increased use of Ginkgo biloba in this population may increase drug-herb interactions. Therefore, we shall examine the effect of Ginkgo biloba on the pancreatic function in the elderly to determine whether it may produce pancreatic dysfunction and a potential for the development of insulinopenia. The results of this study should provide valuable information for designing new therapeutic strategies for the treatment of diseases in the insulin resistance syndrome.

• Kudolo GB. The effect of 3-month ingestion of Ginkgo biloba extract on pancreatic beta-cell function in response to glucose loading in normal glucose tolerant individuals. J Clin Pharmacol. 2000 Jun;40(6):647-54.
• Kudolo GB. The effect of 3-month ingestion of Ginkgo biloba extract (EGb 761) on pancreatic beta-cell function in response to glucose loading in individuals with non-insulin-dependent diabetes mellitus. J Clin Pharmacol. 2001 Jun;41(6):600-11.
• Kudolo GB, Wang W, Barrientos J, Elrod R, Blodgett J. The ingestion of Ginkgo biloba extract (EGb 761) inhibits arachidonic acid-mediated platelet aggregation and thromboxane B2 production in healthy volunteers. J Herb Pharmacother. 2004;4(4):13-26.
• Kudolo GB, Dorsey S, Blodgett J. Effect of the ingestion of Ginkgo biloba extract on platelet aggregation and urinary prostanoid excretion in healthy and Type 2 diabetic subjects. Thromb Res. 2002 Nov 1;108(2-3):151-60.
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Inclusion Criteria:

• Clinical diagnosis of type 2 diabetes mellitus and taking oral diabetes medications - Glucotrol, Glucophage and Actose or Avandia
• Must be able to swallow
• Healthy individuals without diabetes aged 20 to 80 years of age

Exclusion Criteria:

• Type 1 diabetes mellitus
• Type 2 diabetes mellitus taking insulin injections
• Regular use of anti-inflammatory drugs
• Chronic anemia