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Low testosterone
How long after starting testosterone therapy do men typically notice changes in energy or libido?
Improvements in sexual interest and mood often begin within 3 to 6 weeks, while noticeable changes in energy, body composition, and muscle mass typically take several months.
Reviewed by Michael “Ted” Mimlitz, MD · Reviewed 2026-08-31T15:17:06.426056+00:00 · Updated 2026-08-31T15:17:08.880385+00:00