Low-T
Low Testosterone: When to Test and What the Numbers Mean
Suspected low testosterone is confirmed with two morning total testosterone levels on separate days, plus LH, FSH, and prolactin to identify the cause. Treatment is considered when levels are consistently below ~300 ng/dL with classic symptoms (low libido, fatigue, erectile changes). Treatment requires monitoring of hematocrit, PSA, and fertility goals.
Medically reviewed by Dr. Angelo Gousse, MD — board-certified urologist (Florida).
Who should be tested
Men with persistent low libido, ED unresponsive to PDE5 inhibitors, fatigue, depressed mood, or loss of muscle mass should be evaluated. Routine screening of asymptomatic men is not recommended.
Treatment considerations
Therapy is individualized — gels, injections, or pellets. Fertility-preserving options (clomiphene, hCG) are preferred for men who want children. PSA and hematocrit are monitored every 3–6 months in the first year.
Frequently asked questions
- Does testosterone therapy cause prostate cancer?
- Large modern studies do not show that therapy causes prostate cancer, but it should not be started in men with active prostate cancer without specialist input.