Phase II Studies Of Donepezil And Ginkgo Biloba In Irradiated Brain Tumor

DISEASE CHARACTERISTICS: * Diagnosis of primary brain tumor or brain metastases, meeting 1 of the following criteria: * No radiographic evidence of disease * Stable disease, defined as no tumor progression within the past 3 months * Previously treated with 1 course of localized or whole brain radiotherapy of at least 3,000 cGy at least 6 months before study registration PATIENT CHARACTERISTICS: Age * 18 and over Performance status * Karnofsky 70-100% Life expectancy * At least 30 weeks Hematopoietic * Not specified Hepatic * Not specified Renal * Not specified Other * Not pregnant or nursing * Negative pregnancy test PRIOR CONCURRENT THERAPY: Biologic therapy * Not specified Chemotherapy * No concurrent chemotherapy Endocrine therapy * Concurrent steroid therapy allowed if on stable or decreasing dose Radiotherapy * See Disease Characteristics * No concurrent cranial radiotherapy Surgery * No concurrent surgery Other * More than 3 months since prior donepezil or EGb761 * No concurrent donepezil (group 2 only) * No concurrent EGb761 (group 1 only) (closed to accrual 10/09/03) * No concurrent anticoagulants (e.g., aspirin, dipyridamole, heparin, warfarin, or enoxaparin) (group 2 only) * No concurrent monoamine oxidase inhibitors (e.g., phenelzine or tranylcypromine) * No other concurrent therapy