p Product details of 21st Century Ginkgo Biloba 500mg 30's21ST CENTURY'S Standardized Ginkgo Biloba Extracts, the extract from the oldest living tree in the world, contains 24% gingkoflavonglycosides, the active ingredient which has been established as a brain nutrient. It improves memory and concentration by increasing the blood circulation in the brain and in the extremities of the body - hands and feet. So those with numb hands and feet should take Ginkgo Biloba. For 'ringing in the ear' - tinnitus - Ginkgo Biloba by increasing blood circulation in the head helps reduce the annoying ringing that many people suffer from. In fact this is the only effective treatment for tinnitus - there are no drugs for this condition. Only Ginkgo Biloba (take one capsule twice a day - one in the morning and one at night for tinnitus). /p