In Detail
The timeline for testosterone therapy is well-characterized. Mood, energy, and libido often improve in the first 3 to 6 weeks. Erectile function, when it is going to respond, generally improves over 3 to 6 months. Changes in body composition — increased lean mass, decreased fat mass — typically take 3 to 12 months and depend heavily on training and nutrition.
Bone density changes are slower still, accruing over 6 months to 2 years. Improvements in insulin sensitivity and cardiovascular markers depend on the baseline picture and lifestyle factors.
Patients who do not feel improvement after 3 months should be reassessed. Sometimes the dose is too low, sometimes estradiol management needs adjustment, and sometimes other contributors — sleep apnea, untreated mood disorder, thyroid disease — were the dominant problem.