TRT Timeline: What Changes When, From Week 3 to Year 1

This page orders the trial findings by time on treatment: the Saad review of timing, the Testosterone Trials in men 65 and older, the TRAVERSE heart safety trial, and the AndroGel label (revised 10/2025 on DailyMed). Patient videos appear further down as illustration only. TRT is for men with confirmed low testosterone; a blood test comes first, and our testosterone test cost guide covers that step.

The TRT timeline, from the trials

Weeks 3 to 6: libido first

Sex drive is usually the first thing men notice. The Saad review, which pooled timing data from published trials, reports "Effects on sexual interest appear after 3 weeks plateauing at 6 weeks, with no further increments expected beyond" (Saad et al. 2011). Erections are slower: "Changes in erections/ejaculations may require up to 6 months." Low testosterone is only one cause of erectile problems, so TRT may not fix them at all.

Weeks 3 to 30: mood and energy

Mood moves more slowly than libido. The review found "Effects on depressive mood become detectable after 3-6 weeks with a maximum after 18-30 weeks" and "Effects on quality of life manifest within 3-4 weeks, but maximum benefits take longer" (Saad et al. 2011).

Energy is where trial results disappoint most. In the Testosterone Trials, a year of testosterone gel in men 65 and older "had a moderate benefit with respect to sexual function and some benefit with respect to mood and depressive symptoms but no benefit with respect to vitality or walking distance" (Snyder et al., NEJM 2016). Those were older men, so younger men may respond differently, but the trial is the best placebo-controlled data on fatigue that we have.

Months 3 to 12: body composition

Changes in the mirror take months. The review reports "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" (Saad et al. 2011). Bone is slower again: "Effects on bone are detectable already after 6 months while continuing at least for 3 years." Training and diet shape these results at least as much as the hormone.

Month 3 onward: hematocrit and the blood checks

Testosterone raises red blood cell production, and this is the main reason for follow-up labs. The review found "Effects on erythropoiesis are evident at 3 months, peaking at 9-12 months" (Saad et al. 2011). In men with anemia that can help: in the Testosterone Trials, more treated men with unexplained anemia saw hemoglobin rise "(54%) than did placebo (15%)" (Roy et al., JAMA Intern Med 2017).

In men without anemia it can overshoot. The AndroGel label says "Check hematocrit prior to initiating treatment. It would also be appropriate to re-evaluate the hematocrit 3 to 6 months after starting treatment, and then annually" (DailyMed: AndroGel 1.62% label). It also lists monitoring of "serum testosterone, prostate specific antigen (PSA), hemoglobin, hematocrit, liver function tests and lipid concentrations periodically". A program that prescribes TRT without these labs is skipping the label.

The long view: heart safety and blood pressure

TRAVERSE followed 5,246 men with heart disease or high heart risk. A major cardiac event "occurred in 182 patients (7.0%) in the testosterone group and in 190 patients (7.3%) in the placebo group", though "A higher incidence of atrial fibrillation, of acute kidney injury, and of pulmonary embolism was observed in the testosterone group" (Lincoff et al., NEJM 2023). After the trial, the FDA moved to remove the boxed cardiovascular warning while adding "a new warning about increased blood pressure for testosterone products which currently do not have such a warning in their labeling" (FDA, February 2025).

What the videos show

TRT videos tend to follow a pattern: week one hopes, a month-two update on libido and sleep, a six-month physique comparison. They are individual experiences, not evidence. Many creators also train hard, diet and sometimes use other compounds, so a video cannot separate the hormone from everything else.

Urologists answer your questions about testosterone replacement therapy | TRT
Rena Malik, M.D., December 7, 2021Testosterone & Testosterone Replacement Therapy (TRT) | Dr. Peter Attia & Dr. Andrew Huberman
Huberman Lab Clips, August 19, 2022Is Testosterone Safe for Your Heart?! Things You Should Know
Rena Malik, M.D., July 14, 2023

Videos belong to their channels; our summary is on each video's page. All 8 Testosterone therapy (TRT) videos.

More, with our summary of each, are on the TRT video hub.

Which programs let you message a clinician

TRT is a treatment with scheduled labs, so ongoing access to a clinician matters more than for most prescriptions. These are the programs that let you message a clinician, and what it costs.

From each program's own page, read 2026-10-31.

What it costs

The cheapest low testosterone plan we track is Rugiet at $99, checked October 31, 2026. Check what the price leaves out: follow-up labs at 3 to 6 months and then yearly are part of the label, and some programs bill them separately. Every plan is on our TRT price page, and the ranked programs are on Best men's health programs.