I was on 400mg twice in my life for a couple of years. If I had nothing in my stomach I would be crawling up the stairs to bed in 15-30 minutes from taking it. Other nights, when I had food in my belly it could take 1-2 hours, and every once in awhile several hours. It was sedating for me even at high doses (I read the article-good article). Everyone is different I guess. Now I can't sleep worth a crap, even after all the meds prescribed.