Written by Keen Meds  ·  Reviewed by Licensed Clinical Providers  ·  March 1, 2026

Key Insight: Testosterone modulates the HPA axis (hypothalamic-pituitary-adrenal axis), the body's primary stress-response system -- reduced testosterone can increase cortisol sensitivity and anxiety.

> Testosterone modulates the HPA axis (hypothalamic-pituitary-adrenal axis), the body's primary stress-response system -- reduced testosterone can increase cortisol sensitivity and anxiety.

Medically reviewed by licensed clinical providers · March 2026

Anxiety is not the first symptom men associate with low testosterone. Fatigue, libido decline, and muscle loss occupy more space in public awareness. But anxiety -- a persistent sense of unease, elevated baseline worry, or irritability that seems disproportionate to circumstances -- is a recognized and increasingly documented feature of hypogonadism in men. The mechanism is physiologically real. Testosterone has direct regulatory effects on the HPA axis, the system that governs the body's stress response, and on the GABAergic and serotonergic pathways that modulate anxiety tone. When testosterone is low, these systems can shift in a direction that elevates baseline anxiety. This post explains how, reviews the clinical evidence, and describes how to evaluate whether anxiety may have a hormonal component.

The HPA-HPG Axis Connection

The HPG axis (hypothalamic-pituitary-gonadal axis) and the HPA axis (hypothalamic-pituitary-adrenal axis) are the two primary neuroendocrine control systems in men. They interact at multiple levels, and their relationship is largely reciprocal: under normal conditions, testosterone tends to suppress HPA activity, and cortisol tends to suppress testosterone production.

When testosterone levels are adequate, testosterone acts as a functional brake on the HPA axis -- it reduces the sensitivity of the stress response system, modulates cortisol secretion, and promotes a baseline physiological state that is lower in autonomic arousal. This is one reason well-androgenized men often demonstrate greater stress tolerance and lower baseline anxiety than hypogonadal men in clinical studies.

When testosterone falls, that inhibitory influence on the HPA axis weakens. The HPA system becomes more reactive. Cortisol responses to stressors are amplified, cortisol clearance may be slower, and baseline cortisol can drift upward. Elevated chronic cortisol is itself a driver of anxiety, sleep disruption, and central nervous system arousal.

The practical effect is that men with low testosterone may find themselves responding to ordinary stressors with a physiologically disproportionate reaction -- elevated heart rate, heightened worry, difficulty calming down -- without a corresponding increase in objective threat. This is not a psychological weakness; it is a dysregulated neuroendocrine system.

Testosterone and GABAergic Anxiety Regulation

Beyond the HPA-cortisol mechanism, testosterone has direct effects on gamma-aminobutyric acid (GABA) signaling. GABA is the primary inhibitory neurotransmitter in the central nervous system, and GABAergic tone is the primary biological brake on anxiety. Many anxiolytic medications (benzodiazepines, pregabalin) work by enhancing GABA activity.

Testosterone and its neuroactive metabolite allopregnanolone modulate GABA-A receptor activity. In adequate concentrations, testosterone supports GABAergic inhibitory tone, which reduces baseline anxiety. When testosterone is low, this support is reduced, and the excitatory-inhibitory balance in the CNS shifts toward higher anxiety.

Additionally, testosterone receptors in the amygdala -- the brain region most central to fear processing and threat response -- have been shown to modulate threat appraisal. Low testosterone is associated with heightened amygdala reactivity to ambiguous stimuli, meaning the brain is more likely to interpret neutral or low-threat situations as threatening. This neurobiological finding maps directly onto the clinical picture of anxiety with no obvious external cause.

The Clinical Presentation: Anxious But Don't Know Why

Men with hypogonadism-related anxiety often present with a characteristic pattern that differs from classical anxiety disorders in a few ways:

  • The anxiety is not focused on specific external threats or situations (as in phobias or social anxiety disorder)
  • It is not driven by specific intrusive thought content (as in OCD)
  • It is more of a free-floating unease, restlessness, and heightened baseline arousal
  • It is frequently accompanied by irritability, a low frustration threshold, and a shortened temper that men often attribute to stress rather than hormonal change
  • It is commonly paired with sleep disruption -- difficulty falling asleep due to a racing mind or physiological arousal that will not settle
  • It often began gradually over months to years, without a precipitating life event

This gradual onset without clear external cause is an important clinical signal. When a man cannot identify why he feels more anxious than he used to be, and the anxiety appeared at roughly the same time as fatigue, libido changes, or physical performance decline, hormonal evaluation is warranted.

Clinical Evidence for TRT and Anxiety Reduction

Several studies have documented reductions in anxiety scores in hypogonadal men following testosterone therapy. The TRAVERSE trial depression and mood sub-study, which used validated psychological instruments, found improvements in mood and psychological well-being in the testosterone arm compared to placebo. Anxiety symptoms are often captured within these broader mood assessment tools.

Earlier smaller trials using validated anxiety scales (including the Hamilton Anxiety Rating Scale) have shown statistically significant anxiety reduction in hypogonadal men following TRT initiation. The effect appears most pronounced in men with confirmed hypogonadism at baseline, consistent with the hypothesis that TRT is correcting a hormonal deficit that underlies the anxiety rather than simply providing pharmacological suppression.

Animal models have also been instructive. Testosterone administration in adrenalectomized and gonadectomized rodent models consistently reduces anxious behavior, with effects reversed by androgen receptor blockade -- suggesting a direct androgen-receptor-mediated mechanism.

Differentiating Hormonal from Primary Psychiatric Anxiety

Hormonal anxiety and primary anxiety disorders (GAD, panic disorder, social anxiety, PTSD) are not mutually exclusive and can coexist. The following features suggest a hormonal component is worth investigating:

  • Age 35 or older, with gradual onset
  • Other symptoms of hypogonadism present (fatigue, libido decline, muscle loss, cognitive slowing)
  • Anxiety did not respond fully to standard anxiolytic treatment (therapy, SSRIs, SNRIs)
  • No clear psychosocial precipitant for the anxiety onset
  • Morning cortisol elevated on standard panel
  • Family history of hypogonadism or early testosterone decline

A morning fasting testosterone measurement is a low-cost, low-risk step that can either confirm or rule out a hormonal contributor. When anxiety is present alongside other hypogonadism symptoms and has not responded to standard approaches, a hormone panel that includes testosterone, free testosterone, SHBG, and cortisol provides the most informative initial picture.

What TRT Does for Anxiety in Clinical Practice

Men with confirmed hypogonadism who start TRT and have anxiety as a component of their symptom picture often report reductions in baseline irritability and generalized worry within 4 to 8 weeks. Sleep quality improvement -- frequently noted early in TRT -- tends to reduce the sleep-deprivation component of anxiety, which reinforces improvement.

The physiological changes described above -- HPA axis downregulation, improved GABAergic tone, reduced amygdala reactivity -- are not instantaneous. Sustained reduction in anxiety is most reliably observed after 3 to 6 months of stable testosterone levels in the therapeutic range (400 to 700 ng/dL). Men who also engage behavioral interventions (exercise, sleep hygiene, stress management) tend to show faster and more durable improvement.

TRT is not a first-line treatment for primary anxiety disorders and should not be presented as such. Its role is hormonal correction in men whose anxiety has a documented hormonal component.

Frequently Asked Questions

Is it normal to feel more anxious as testosterone drops with age?
Gradual increases in baseline anxiety as testosterone declines with age are documented in epidemiological data, though not universal. The roughly 1 to 2% annual decline in testosterone after age 30 means that men in their mid-40s and beyond may have testosterone levels meaningfully lower than their younger selves -- and the HPA axis changes that accompany this decline can raise anxiety tone over time. This is not an inevitable outcome of aging, but it is a recognized pattern that warrants investigation when anxiety increases without clear explanation.

Can checking cortisol help identify whether my anxiety is hormonal?
Yes. A morning serum cortisol level, drawn alongside testosterone, can identify whether HPA axis dysregulation is contributing to anxiety. Elevated morning cortisol in combination with low testosterone is a recognized pattern in hypogonadism and supports a hormonal explanation for anxiety symptoms. Cortisol alone is not diagnostic, but the combined hormone picture informs clinical decision-making.

Will TRT make anxiety worse before it gets better?
A small number of men report a brief period of increased restlessness or agitation in the early weeks of TRT, which is believed to reflect the initial hormonal adjustment period. This is not universal and typically resolves as levels stabilize. Men with a history of significant anxiety should discuss this possibility with their clinical provider before starting therapy so appropriate monitoring is in place.

Is Anxiety Part of Your Low Testosterone Picture?

If anxiety, irritability, or a persistent sense of unease is part of a pattern -- alongside fatigue, low mood, poor sleep, or reduced motivation -- low testosterone may be a contributing factor. A blood test is the only way to confirm.

Keen Meds connects you with a licensed clinical team for a telehealth consultation and lab review. If your testosterone is clinically low, you receive a prescription for Testosterone Spray Rx -- delivered via Hypospray®, Keen's needle-free transdermal spray platform.

Start your Keen Testosterone Spray Program →

Medically reviewed by Licensed Clinical Providers · March 2026

Related reading: