How is low testosterone diagnosed?

Testosterone levels are assessed using a blood test. The cutoff for low testosterone differs between organizations, but most define it as a total testosterone level of <231–275 ng/dL.^[1] Testosterone levels should be assessed early in the morning (between 7–11 a.m.) when peak levels occur, and in a fasted state. Two separate low testosterone measurements (preferably four weeks apart) along with clinical signs and symptoms of low testosterone are needed to be diagnosed with low testosterone.