Clen works great for me, but only for a short time. Everyone's body is different, and I notice that my body temperature stops going up after just a week or so of using Clen. Therefore, I take a couple weeks off, and then either use an ECA stack before breaking again or going back to the Clen. Make sure you find the right dose for you as well, as too little won't accomplish your goals if you're not exercising, working out, and dieting hard, and too much will keep you up at night staring at the ceiling beings the Clen stays in your system longer than a day, which is a pain if you're taking too much and compounding it daily. At least for me it works this way. I have friends who can't stand 60 mgs daily of the stuff, and I'm more tolerant to stimulants and find that 140 mgs daily is the perfect amount for me. I've never tried the Benedryl for regulation of the receptors as someone recommended, but will certainly look into it. Again, I think everyone's body is different, as everyone I know and work out with takes Clen differently. Find what's best for you to accomplish your goals, and stick with it.