Some frequently used medications increase dementia risk in older people. These drugs, which are used to treat common disorders such as asthma, depression and incontinence, have anticholinergic (AC) activity—that is, they block an important neurotransmitter called acetylcholine. They include brompheniramine (Dimetapp), chlorpheniramine (Chlor-Trimeton), diphenhydramine (Benadryl), doxylamine (Unisom), oxybutynin (Ditropan) and paroxetine (Paxil).
Recent finding: Older people who regularly took an AC drug had brain cavities up to 32% larger than other seniors. Increased cavity size reflects brain atrophy. AC-medication users also did worse on tests of brain function including short-term memory, verbal reasoning, planning and problem solving.
Self-defense: Older people who use an AC drug for a chronic condition should ask their physicians whether non-AC alternatives are available. A list of medications that have possible or definitive AC properties can be found by putting “Anticholinergic Burden (ACB) Scale” into any search engine. Drugs with an ACB score of 3 (found in the right-most column) are the most problematic.