Solomon PR, Adams F, Silver A, et al. Ginkgo for memory enhancement. JAMA. 2002;288:840.
A double-blind, placebo control study was conducted to determine if ginkgo was effective for memory enhancement. The researchers enrolled 230 volunteers between 60 and 82 years of age. Volunteers were randomly assigned to either one of two groups (placebo or ginkgo). The gingko selected was from one manufacturer. Doses were within recommend norms.
One day before the medication trial, 14 different neuropsychological tests of learning, memory, attention, and concentration were administered. At the end of the 6-week trial the tests were repeated. In addition, participants completed a questionnaire regarding their impression of the state of their memory. A companion designated by each participant was asked to complete a form to indicate any perceived change in the participant's memory.
There were no statistically significant differences between the drug and placebo groups on any of the neuropsychological tests. Companions rated the participants as having minimal improvement or no change in memory. There was no significant difference in participants' self-assessment of their memory.
The researchers believed their study clearly demonstrated that the manufacturer's claims regarding the cognitive benefits of gingko with respect to learning and memory could not be supported either by psychometric exam, self-report, or observation.
Frankish H. Ginkgo biloba does not enhance memory in healthy adults US study finds. Lancet2002;360:623.
The results of the aforementioned study by Solomon, et al., in JAMA are reviewed. In addition, a brief interview with Solomon is included. Steven Ferris, of the Silberstein Institute for Aging and Dementia, comments on the conclusions. The findings are believed to be an indicator not of the lack of benefits of gingko but of a need to better regulate available herbal products.
Bhattaram VA, Ulrike G, Kohlert C, et al. Pharmacokinetics and bioavailability of herbal medicinal products. Phytomedicine. 2002;9(suppl III):1-33.
This supplement of the journal Phytomedicine provides information regarding the pharmacokinetics and bioavailability of six herbal medicinal products (HMPs), including ginkgo and St. John's wort. Possible drug interactions and serious medical side effects are also presented. Information is supported by an extensive bibliography. This supplement can serve as a good resource tool for the clinician called upon to review the efficacy of patient use of herbal products.