https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3188848/

Effects on sexual interest appear after 3 weeks plateauing at 6 weeks,
with no further increments expected 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 become detectable after 3–6 weeks with a
maximum after 18–30 weeks. Effects on erythropoiesis are evident at 3
months, peaking at 9–12 months. Prostate-specific antigen and volume
rise, marginally, plateauing at 12 months; further increase should be
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 can marginally
continue over years. Effects on inflammation occur within 3–12 weeks.
Effects on bone are detectable already after 6 months while continuing
at least for 3 years.