The first time I took it I was at work, third day at a new part-time job, standing on my feet. I felt the initial 'high', the rush of 'feel-good' something, and then I felt a bit wobbly, kind of disoriented...I wanted to just go home and fall into bed. Then I was told that I may have taken too much too soon. So the next time I was in a lot of pain (I reserve it for when the pain is level 9-10) I took only a half a pill, followed by the other half about 30-60 minutes later. I don't remember being especially more tired after taking it. I don't take it often, so it's hard for me to tell you. (I've learned what kinds of activities increase my pain level, and so I try to avoid those activities. )
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