BDCC is correct stims can have a negetive effect on libido that is why I always recommend you have a few different stim supplements with different formulas so your body doesn't get use to the same formula every day and I always recommend not using 1, 3, dimeth everyday.I love 1,3, dimeth for my preworkout but I never use it more than twice a week and never on back to back workouts and if you plan ongetting some action from a lady friend a little after your workout I would use a stim without 1,3, dimeth for that workout unless you areusing something like Mesomorph by APS Nutrition which has a few ingredients in it to combat the bad effects of the 1,3, dimeth. I still think if you drop your doseage of Testopro to 4 caps instead of 6 you should be o.k. One thing I noticed about the Testopro was my body composition really hardend up even though I was not on a cut diet. Even though my libido was down a little after 4 weeks of taking Testopro I didn't mind to much because I was still taking in a good amount of clean calories and my body was looking hard as a rock.