If my elderly father is sleeping 16 hours a day can this be the side effect of the medication he is on?

When did he start taking Aricept? Ten years ago? Sleepiness can be a side effect of that drug. My husband takes Aricept and he sleeps about 9 hours a night and occasionally takes a nap. Obviously Aricept doesn't make everyone sleep a lot, but different people have different reactions to drugs. What does his doctor say about the excessive sleepiness?

Aricept is the only drug. Takes vitamins/minerals. Been sleeping a lot last 10 years, so it's not new.

Oh, sorry, you already answered about the diagnosis -- ALZ. What other drugs is he taking?

When did he start taking aricept? How many hours a day was he sleeping before that? What is his diagnosis?