I am always on test when I run it. I don't notice a decrease in sex drive. I just start looking grainy, very dry looking. Almost looks like I cut carbs for a week or so and didn't load up again. My training partner complains about a low sex drive, but I dont notice it. I just feel very dry and flat. Its too strong for the amount of test I usually run (500-800mg) I stick with arimidex because I like the fuller look and test doesnt really aggrevate my gyno.