A review of studies attempted to determine the time-course of the effects induced by testosterone replacement therapy from their first manifestation until maximum effects are attained.
This review found that:
· Effects on sexual interest appear after 3 weeks plateauing at 6 weeks, no further increments beyond.
· Changes in erections/ejaculations may require up to 6 months.
· Effects on quality of life manifest within 3-4 weeks, but maximum benefits take longer.
· Effects on depressive mood appear after 3-6 weeks with a maximum after 18-30 weeks.
· First effects on erythropoiesis (increased red blood cells) after 3 months, peaking at 9-12 months.
· Prostate specific antigen and volume rise, marginally, plateauing at 12 months; further increase related to aging rather than therapy.
· Effects on lipids appear after 4 weeks, maximal after 6-12 months.
. Insulin sensitivity may improve within few days, but effects on glycemic control become evident only after 3-12 months.
· Changes in fat mass, lean body mass and muscle strength occur within 12-16 weeks, stabilize at 6-12 months, but marginally continue to improve over years.
. Effects on inflammation occur within 3 to 12 weeks.
· Effects on bone detectable after 6 months but continue at least for 3 years.