Anticholinergics such as diphenhydramine (aka Benadryl) and doxylamine do work well, but long-term safety is in doubt....
Antihistamines are some of the most popular and most used drugs in the world. It sucks to have to take a drug to get good sleep, but if you have to take one, antihistamines are probably the best choice available.
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Common Meds and Dementia: How Strong Is the Link?