I took this medication after outpatient surgery before going to b...

I took this medication after outpatient surgery before going to bed and could not get to sleep. By 3:00 A.M. I was dizzy, almost fainted, panting, and had extreme hot feeling under my skin which started in my arms. Thank God I was staying at my daughters and was able to wake her up for help. She put ice cold tea towel on back of my neck got me to take deep breaths, and put my head between my legs. Within few minutes I began to stablized but was and am still screwed up from it after 6 days. I also suffered constipation for 4 days after taking it. I'd be very leary of this drug. I'm currently on blood pressure and thyroid medication so I don't know if there was some type of interaction with them or what. Very unpleasant. It through me into horrible panic attack. Barb