my only real concern while on clen is the heart risks associated with it. i've tried clen, and it worked pretty good for me. however, i've heard combining it with t3 makes it far more effective. now, although t3 doesn't seem to adversely affect the heart from it's list of side-effects, does it increase the risks to the heart that clen gives you cause of them amplifying each others effects? i would like to try this combo down the road, but messing with my heart is one thing i'm not a big fan of.