Cognitive enhancers, such as donepezil or rivastigmine, do not improve function in those who have mild cognitive impairment over the long term, new research reveals.

After studying eight randomized trials with four cognitive enhancers, which also included galantamine or memantine, researchers at St. Michael’s Hospital in Canada found patients had more nausea, diarrhea, vomiting and headaches. While there was a short-term benefit, the drugs did not help cognition over longer periods.

Certain cognitive enhancers are approved to treat Alzheimer’s, but there is increased demand for those with mild cognitive impairment, the researchers noted. While the cognitive enhancers can only be obtained in Canada with special authorization, the researchers said families and patients are increasingly requesting these medications without the full picture. 

“Our results do not support the use of cognitive enhancers for patients with mild cognitive impairment,” wrote the authors, Andrea Tricco, Ph.D., M.Sc., and Sharon Straus, M.D., H.B.Sc., M.Sc. 

Results were published in September in the Canadian Medical Association Journal