sedation
"Tried 50 mg tablet at 8:30; felt nothing. Then took another 50 mg at 9:30 and didn't feel like it helped much either. Then in the morning, I was completely groggy and out of it all day; felt like a zombie. Next night, I took one 50 mg, and I definitely never fell asleep any faster. It might make you feel drowsy, but it didn't help promote sleep."