I was diagnosed with low testosterone at the age of 28-years-old with levels as low as 231 ng/dl. My doctor prescribed Androgel for me and I immediately began using it on a daily basis. I took it for about a year and a half and have become quite dependent on it. Recently I changed insurance plans and started to see a new doctor. I told him that I wanted to be tested for all kinds of levels including LH, FSH, SHBG, cortisol, estrogen, and prolactin. He told me that in order to get a good idea of where I was at on these levels that I would have to stop taking testosterone for six months. From there, he said, we can run the blood tests and know where the levels are. I have two questions. First, is it true that I need to stop taking testosterone to check my levels of all these various hormones? Second, if I do need to stop taking testosterone to be tested, does anyone have any references that indicate how long I need to wait to make sure the levels are accurate? My doctor admitted that even he did not know exactly how long I need to wait but that he thinks it is about six months. I'd like to have a more definite answer or some kind of reference or evidence that recommends a time period. I am going to try to make it six months without testosterone but I remember how difficult it was to concentrate before and I am worried because I need to be able to concentrate at work. Any help is very much appreciated.