Testosterone can help reduce depressive symptoms in some men, particularly those with clinically low levels. A large meta-analysis of 27 randomized controlled trials covering 1,890 men found that testosterone treatment produced a statistically significant reduction in depressive symptoms compared to placebo. But the effect was modest, and the benefit depends heavily on who’s receiving it and why.
How Testosterone Affects Mood
Testosterone doesn’t act on mood the way most people assume. It doesn’t directly stimulate the brain’s serotonin system, the same system targeted by common antidepressants. Instead, testosterone gets converted into estradiol (a form of estrogen) in the brain, and estradiol then interacts with serotonin-producing neurons. This indirect route means testosterone’s mood effects are real but more complex than simply “more testosterone equals better mood.”
The serotonin system plays a central role in regulating mood, stress response, sleep, and appetite. By influencing serotonin signaling through this conversion process, testosterone helps maintain emotional stability. There’s also evidence that testosterone supports the growth of new brain cells, which may independently contribute to its antidepressant effects. These pathways help explain why men with very low testosterone often experience mood changes, and why restoring normal levels can improve how they feel.
The Link Between Low Testosterone and Depression
Depressive symptoms show up in 35 to 50 percent of men with clinically low testosterone, a rate far higher than in the general male population. The relationship runs both directions: low testosterone increases the risk of depressive symptoms, and depression itself can suppress testosterone production. This creates a cycle that can be difficult to break with a single intervention.
That said, low testosterone does not automatically cause major depressive disorder. When researchers control for other risk factors like unemployment, social isolation, and substance use, the connection between below-average testosterone and depression weakens for some groups. The clearest link exists in men whose levels fall well below the normal range, not in men sitting at the lower end of normal.
Who Benefits Most From Treatment
The strongest evidence for testosterone’s antidepressant effect comes from men with confirmed low levels, generally below 12 nmol/L (about 346 ng/dL) on morning blood tests. British Society for Sexual Medicine guidelines list depressed mood as a recognized symptom of testosterone deficiency, and treatment is recommended when symptoms align with low lab results confirmed on two separate occasions.
Certain subgroups show especially promising responses. Men with treatment-resistant depression who haven’t improved on standard antidepressants, men living with HIV, and men with a chronic low-grade form of depression called dysthymia have all shown meaningful improvement with testosterone therapy in clinical studies. In one small but striking study, five men with low testosterone who had failed to respond to antidepressants experienced rapid and dramatic recovery after starting testosterone: their depression scores dropped by more than 60 percent within two weeks and continued improving over eight weeks. Three of the four men who later stopped testosterone under observation began relapsing.
For men with testosterone levels already in the normal range, the picture is much less clear. Some analyses suggest that higher doses might still improve depressive symptoms in these men, but individual studies have found no significant mood changes when eugonadal (normal-level) men received testosterone. The current evidence does not support using testosterone as an antidepressant for men whose hormone levels are already healthy.
What About Women?
Researchers have explored whether low-dose testosterone could help women with depression that hasn’t responded to antidepressants. An eight-week randomized trial tested transdermal testosterone in women with treatment-resistant major depressive disorder, including both premenopausal and postmenopausal participants. The result: testosterone was well tolerated but performed no better than placebo for depression, fatigue, or sexual dysfunction. The treatment effect didn’t differ based on women’s baseline testosterone levels or menopausal status. It’s possible that a more specific population of postmenopausal women with particularly low levels might respond differently, but for now, the evidence doesn’t support testosterone therapy for depression in women.
How Long Until Mood Improves
If testosterone therapy is going to help, early signs typically appear within three to six weeks. Some studies have detected measurable improvement as soon as three weeks, while others using standardized depression rating scales found significant changes at six to eight weeks. Full benefit takes longer. Maximum improvement in depressive symptoms generally occurs between 18 and 30 weeks, meaning you’d need several months of consistent treatment to know the full extent of its effect.
This timeline matters for setting expectations. A three-week check-in might reveal early improvement, but deciding the treatment isn’t working after a month would be premature. Most clinicians reassess after several months before concluding whether testosterone is contributing meaningfully to mood.
Risks and Limitations
Testosterone’s relationship with mood isn’t a straight line where more is better. Both high and low levels are associated with increased rates of depression and mood instability. Supraphysiological doses (levels pushed above the normal range) have been linked to hypomanic symptoms: elevated energy, reduced need for sleep, impulsivity, and irritability. One dose-ranging study that gave older men weekly injections at five different doses, from 25 mg up to 600 mg, found no dose-dependent improvement in depression scores at all, reinforcing that simply pushing levels higher doesn’t reliably improve mood.
The overall effect size from the largest meta-analysis was a Hedges’ g of 0.21, which translates to a small but real effect. For comparison, standard antidepressants typically show effect sizes in the range of 0.3 to 0.5. Testosterone therapy is not a replacement for established depression treatments. It works best as an additional tool for men whose depression coexists with genuinely low hormone levels.
Men taking long-term opioid painkillers, antipsychotics, anticonvulsants, or certain acne and hair-loss medications are at higher risk for developing low testosterone and should be screened. If you’re on one of these medications and experiencing depressive symptoms, the depression could be partly driven by medication-induced hormone changes rather than a primary mood disorder.