The symptom overlap
Major depressive disorder and hypogonadism share substantial symptom overlap:
| Symptom | Depression | Low T |
|---|---|---|
| Low mood | Yes | Common |
| Low motivation | Yes | Yes |
| Anhedonia | Yes | Yes |
| Fatigue | Yes | Yes |
| Sleep changes | Yes | Yes |
| Concentration | Yes | Yes |
| Irritability | Yes | Yes |
| Low libido | Yes | Yes |
| Erectile dysfunction | Sometimes | Common |
| Reduced muscle / strength | No | Yes |
| Reduced morning erections | No | Yes |
The last two items are differential, present in low T but not typically in depression alone.
Missed diagnosis frequency
Hypogonadism is underdiagnosed in men presenting with mood symptoms:
- Many primary care visits for "depression" don't include T testing
- Men with low T often resist seeking help and present late
- SSRIs are prescribed before hormone evaluation
- Some patients improve modestly on SSRIs without ever knowing they had low T
TRT effect on mood
In men with confirmed low T and mood symptoms:
- Mood improvement at 1-3 months
- Reduced fatigue
- Restored motivation and drive (covered in dopamine article)
- Improved sleep
- Improved sexual function
- Effect size moderate-to-large in deficient men
vs. SSRIs
SSRIs and TRT address different mechanisms. SSRIs increase serotonin and may help mood independent of cause. TRT addresses upstream hormonal cause when low T is the driver.
Some patients on SSRIs for "depression" find that adding TRT (or replacing SSRI with TRT) produces better function than SSRI alone. SSRIs themselves can cause sexual dysfunction that further compounds testosterone-related symptoms.
Comorbid presentation
Many men have both legitimate depression and low testosterone. In these cases:
- Treat both
- SSRI or other antidepressant for the mood disorder
- TRT for the hypogonadism
- Often better outcomes than treating either alone
Evaluation approach
For men presenting with depression-like symptoms:
- Complete clinical evaluation
- Comprehensive hormone panel (total + free T, SHBG, LH, FSH, estradiol, prolactin, thyroid)
- Sleep screening (apnea co-occurs)
- Metabolic markers
- Vitamin D, B12, iron
- Mental health evaluation
The decision about treatment direction depends on what comes back.
The clinical pearl: Don't diagnose depression in men without checking testosterone. The symptom overlap is too substantial. Men labeled and treated as depressed who actually have low T often improve dramatically when the right cause is addressed.
Bottom line
Low testosterone and depression share substantial symptom overlap. Many men with low T are misdiagnosed and treated for depression. TRT in men with confirmed low T often produces mood improvements that antidepressants cannot. For comorbid presentations, treating both produces better outcomes. Hormone evaluation should be part of any persistent mood symptom workup in men.