Ginkgo biloba extract EGb 761(R), donepezil or both combined in the treatment of Alzheimer's disease with neuropsychiatric features: a randomised, double-blind, exploratory trial

Aging Ment Health. 2009 Mar;13(2):183-90. doi: 10.1080/13607860902749057.


Objective: This randomised, double-blind exploratory trial was undertaken to compare treatment effects and tolerability of EGb 761(R), donepezil and combined treatment in patients with AD and neuropsychiatric features.

Method: We enrolled 96 outpatients, aged 50 years or above, who met the NINCDS/ADRDA criteria for probable AD, scored below 36 on the TE4D, a screening test for dementia, below 6 on the Clock-Drawing Test (CDT) and between 9 and 23 on the SKT, a cross-culturally validated cognitive test battery. They scored at least five on the 12-item Neuropsychiatric Inventory (NPI). EGb 761(R) (240 mg per day), donepezil (initially 5 mg, after 4 weeks 10 mg per day) or EGb 761(R) and donepezil combined (same doses) were administered for 22 weeks.

Results: Changes from baseline to week 22 and response rates were similar for all three treatment groups with respect to all outcome measures (SKT, NPI, total score and activities-of-daily-living sub-score of the Gottfries-Bråne-Steen Scale, Hamilton Rating Scale for Depression, CDT and Verbal Fluency Test). An apparent tendency in favour of combination treatment warrants further scrutiny. Compared to donepezil mono-therapy, the adverse event rate was lower under EGb 761(R) treatment and even under the combination treatment.

Conclusion: These exploratory findings helped to develop three hypotheses that will have to be proven in further studies: (1) there is no significant difference in the efficiency between EGb 761(R) and donepezil, (2) a combination therapy will be superior to a mono-therapy with one of both substances and (3) there will be less side effects under a combination therapy than under mono-therapy with donepezil.

Publication types

  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Aged, 80 and over
  • Alzheimer Disease / drug therapy*
  • Alzheimer Disease / physiopathology
  • Alzheimer Disease / psychology
  • Bulgaria
  • Donepezil
  • Double-Blind Method
  • Drug Therapy, Combination
  • Female
  • Ginkgo biloba
  • Humans
  • Indans / administration & dosage
  • Indans / pharmacology
  • Indans / therapeutic use*
  • Male
  • Middle Aged
  • Nootropic Agents / administration & dosage
  • Nootropic Agents / therapeutic use*
  • Outcome Assessment, Health Care
  • Piperidines / administration & dosage
  • Piperidines / pharmacology
  • Piperidines / therapeutic use*
  • Plant Extracts / administration & dosage
  • Plant Extracts / pharmacology
  • Plant Extracts / therapeutic use*


  • Ginkgo biloba extract 501
  • Indans
  • Nootropic Agents
  • Piperidines
  • Plant Extracts
  • Donepezil