Ginkgo extracts appear to be capable of stabilizing and, in some cases, improving the cognitive performance of patients with schizophrenia. Based on a quantitative analysis of the literature there is a small but significant effect of 3 to 6 month treatment with 120 to 240 mg of Gbe on ******************ive measures of cognitive function in Alzheimer's Disease ( Oken, Oregon Health Sciences University, 1998 ). The last publication ( Le Bars, Memory Centers of America, New York, Jan 2002 ) indicated that " a treatment effect favorable to EGb could be observed with respect to cognitive performance and social functioning regardless of the stage of dementia, whether mild or moderately severe. However, the relative changes from baseline measured at endpoint depended heavily on the severity at baseline. Improvement was observed in the group of patients with very mild to mild cognitive impairment, while in more severe dementia, the mean EGb effect should be considered more in terms of stabilization or slowing down of worsening, as compared to the greater deterioration observed with placebo". Further research in the area will need to determine if there are functional improvements and to determine the best dosage. Additional research will be needed to define which ingredients in the ginkgo extract are producing its effect in individuals with AD. A recent study makes clear that EGb treatment may enhance the effectiveness of antipsychotic drugs and reduce their extrapyramidal side effects ( Zhang, Yale University School of Medicine, 2001 ).
2) Cardiovascular Disease: Treatment with Ginkgo biloba extract lowers fibrinogen levels and decreases plasma viscosity ( EGb can limit oxidative stress )
3) Cerebral vascular insufficiency and impaired cerebral performance:
Administration of EGb has been shown to improve a variety of conditions associated with cognitive functions, particularly for memory loss, attention, alertness, vigilance, reaction times and depressive mood. A recent australian study indicates significant improvements in speed of information processing working memory and executive processing attributable to the EGb ( Stough C, Swinburne University of Technology, Melbourne, 2001 ). Other therapeutic applications include:
1) Congestive symptoms of premenstrual syndrome: Ginkgo extract was effective for the treatment of the congestive (particularly breast symptoms) and neuropsychological symptoms of PMS.
2) Intermittent Claudication: A recent meta-analysis ( Pittler, University of Exeter, 2000 ) found a significant difference in the increase in pain-free walking distance in favor of Ginkgo biloba (weighted mean difference: 34 meters ). In studies using similar methodological features (ergometer speed: 3 km/h, inclination: 12%) this difference was 33 meters in favor of Ginkgo biloba.
3) Vertigo / Equilibrium Disorder / Prevention of altitude sickness.
4) Tinnitus (ringing in the ear).
An overview ( Holstein, Karlsruhe, 2001 ) of results of 19 clinical trials shows a statistically significant superiority of treatment with the Gbe 761 as compared with placebo or reference drugs applied of periods of 1 to 3 months. " Therapeutic success was not directly correlated with either the genesis or the duration of tinnitus. However, investigations of prognostic factors revealed that short-standing disorders have a better prognosis, so that better results can be expected from early-onset treatment."
5) Liver Fibrosis:
Ginkgo biloba was shown to be effective in arresting the development of liver fibrosis associated with chronic hepatitis B.
6) Macular degeneration:
In spite of the small population sample, a statistically significant improvement in long distance visual acuity was observed in patients with macular degeneration.