I have been on Ambien for a year, and have less daytime energy all the time. I suspect it might be related to Ambien use every night. I went off it about 3 weeks ago. Now I fall asleep around daylight. Sometimes I make myself get up, but other days, I sleep til mid afternoon. Several times I have forced myself to stay up all day, missing a whole night of sleep, so that I will sleep well the following night. I do, I crash by 11 and sleep 14 or more hours, still not waking til afternoon, then up until dawn again. I hate it, but Im trying to just be patient with myself.