This is critical to understand, because the lowered libido can cause erectile dysfunction in and of itself. It has happened a number of times on the Peak Testosterone Forum where men have said that their testosterone has been boosted to 800 ng/dl or more and yet they have no sexual desire. This can create anxiety, boredom, etc. for a man and possibly lead to psychogenic erectile dysfunction. Standard testosterone therapy is generally, though certainly not always, quite the opposite and increases libido in a dose dependent manner. You can read more about here: Testosterone and Libido. Again, Clomid can powerfully activate estrogen receptors in the male brain, and this can cause signficant issues for some men.
2. Clomid Failure or Fade. Some men take Clomid and assume that their low testosterone will increase to high levels. However, this is certainly not always the case. Their testosterone may be sitting in the 200-300 ng/dl range and after taking Clomid, their testosterone may only move up to 400 or 450. If a man has outflow issues – see my page on Venous Leakage for more information – then this may not be enough to solve his problems. In addition, he may not be getting the boost in libido and decrease in insulin levels that he needs to really increase his erectile strength and endothelial function.
I should also mention that Clomid can sometimes “fade” in efficacy. Men will start out as high responders with relatively high testosterone levels, only to find that their testosterone begins to fall as the months go by. I have never read a good explanation as to why this happens, but a number of men have reported it.
3. An Overly High Dose. Many doctors do not know that there is a low dose option that works very well with many men with a typical protocol being 12.5 mg MWF. Men who are high responders, and a lot of young guys are in particular, will go quite high with this lower dose. Unfortunately, many physicians start their male patients on dosages of 50 mg per day! This is much more likely to increase the side effects of Clomid (visual disturbances, headaches, decreased mood, etc.) and lowered libido. So a man may be able to improve his erectile strength simply by going to a much more reasonable dose.