A link has already been identified between the use of benzodiazepines and Alzheimer's disease.
Now it looks as though there's another type of drug that's often taken as a sleep aid that can be linked to dementia: antihistamines (and more specifically, diphenhydramine).
This latest study by researchers at the University of Washington examined the health of nearly 3,500 individuals over the age of 65.
None of these individuals showed signs of dementia at the start of the study.
After looking at the medical and pharmacy records of these individuals, researchers estimate that those who take at least 4mg of diphenhydramine per day for more than 3 years are at a greater risk of developing dementia.
Previous studies have also found that antihistamines can damage attention and information processing.
There's no proof that these drugs cause dementia but until further research is undertaken it's worth being aware of the link and sticking to the lowest dose for the shortest time possible.
Source: JAMA Internal Medicine
Last updated: January 28, 2015