The over-the-counter painkiller acetaminophen may help elderly adults with dementia become more active and socially engaged, the results of a small study suggest.Researchers found that when they gave acetaminophen to nursing home patients who had moderate to severe dementia, the medication helped changed some of the patients’ behaviors. They tended, for example, to spend less time in their rooms and more time watching television, listening to music, reading or performing “work-like” activities.The findings suggest that unrecognized, untreated pain in dementia patients keeps them from being as active as they can be, according to the study authors, led by Dr. John T. Chibnall of the Saint Louis University School of Medicine in Missouri.