A double blind placebo controlled trial of ginkgo biloba extract in acute cerebral ischaemia.
A double blind placebo controlled trial was conducted in 55 patients of acute ischaemic stroke. Twenty one and twenty six patients were randomly allotted in group A and group B respectively. In group A, the patients received 40 mg Ginkgo biloba extract at 6 hourly intervals along with routine management. The placebo tablets were dispensed in the tablet form of same size, shape and colour and were given in the same way. After the patients were subjected to computerized tomographic (CT) scan to confirm acute ischaemic infarction, they were assessed on Mathew's scale and reassessed, at 2 weeks and 4 weeks of drug/placebo administration. Both groups showed significant improvement in Mathew's scale score after 2 weeks and 4 weeks. The difference in degree of change was negligible (p > 0.05) in either group. Estimation of relative changes of neurological deficit based on baseline values also showed negligible (p > 0.05) difference. A trial of Ginkgo biloba extract within 6 hours of stroke in a larger dose and in larger sample could be beneficial clinically in patients of cerebral ischaemic infarct, and needs further study. The usefulness of the plant extract has been demonstrated clinically and experimentally in more than 40 trials of chronic cerebral ischaemia, done elsewhere. This was not evident in our study as our study group was different (more than 48 hours after stroke). There appears to be no contraindication or adverse effect of this medication (Ginkgo biloba) in acute ischaemic stroke.
There was no convincing evidence from trials of sufficient methodological quality to support the routine use of Ginkgo biloba extract to promote recovery after stroke. High-quality and large-scale randomised controlled trials are needed to test its efficacy.