Cimetidine+Opiates

[B-Tron]

I've heard that taking the heartburn medication cimetidine before doing opiates will intensify the effects. I found an old box of tagamet HB in my med. closet and took two about 30 min before i railed 20mg of oxy(just enough to give me a buzz) Well bout an hour later it felt like i had been eating valium all day. I could barely keep my eyes open and my concentration was shot to hell, seeing double and having to really try not to fall asleep...I was high, but it didnt feel the same. Could it have potentiated the oxy that much or is there some other reason it hit me like that.I know that tagamet is an anti-histamine and can cause sedation at high doses but i only took 2 and did 20mg of oxy. I ended up feeling really tired all day even after the oxy wore off. Has anyone else tried these 2 together and experienced a smiliar reaction? and if so, did it feel like the tagamet potentiated the high? Any feedback would be very much appreciated. Thanks you guys.