Testosterone replacement therapy (TRT) can significantly influence mood and emotional regulation, though responses vary widely between individuals. When prescribed for confirmed hypogonadism, testosterone treatment often improves mood stability, reduces irritability, and enhances overall emotional wellbeing. However, the relationship between testosterone and emotions is complex—whilst correcting genuine deficiency typically alleviates mood symptoms, inappropriate dosing or fluctuating hormone levels may trigger emotional instability. Understanding how testosterone affects the brain's emotional processing centres, recognising common mood changes during treatment, and knowing when adjustments are needed helps optimise both physical and psychological outcomes. This article explores the emotional effects of testosterone therapy and provides practical guidance for managing mood-related side effects.

How Testosterone Treatment Affects Mood and Emotions

Testosterone replacement therapy (TRT) can influence emotional regulation and mood, though effects vary considerably between individuals. Testosterone acts as a neuroactive steroid that crosses the blood-brain barrier, interacting with androgen receptors in brain regions involved in emotional processing, including the amygdala, hippocampus, and prefrontal cortex. These interactions may influence neurotransmitter systems involved in mood regulation.

When testosterone levels are optimised through treatment for confirmed hypogonadism (low testosterone), many patients report improvements in mood, reduced irritability, and enhanced emotional wellbeing. However, the relationship between testosterone and emotions is not straightforward. The therapeutic window matters significantly: whilst correcting genuine testosterone deficiency often alleviates mood symptoms such as depression and anxiety, supraphysiological doses or rapid fluctuations in testosterone levels may trigger emotional instability.

Key factors influencing emotional responses include:

• Baseline testosterone levels – Men with clinically low testosterone often experience mood improvements when levels normalise

• Dosing regimen – The method of administration (injections, gels) affects how steadily testosterone levels remain, with more stable levels generally associated with fewer mood fluctuations

• Individual sensitivity – Genetic variations in androgen receptor expression and enzyme activity (such as aromatase, which converts testosterone to oestradiol) create person-specific responses

• Pre-existing mental health conditions – Those with underlying mood disorders may experience different effects compared to individuals without such histories

Whilst testosterone therapy is generally well-tolerated when appropriately prescribed and monitored, mood changes including irritability, aggression, and mood swings are recognised potential side effects listed in product information. Rarely, more significant psychiatric effects can occur, particularly in those with pre-existing mental health conditions.

Common Emotional Changes During Testosterone Therapy

Patients undergoing testosterone replacement therapy may experience a spectrum of emotional changes, both positive and potentially challenging. Understanding these common responses helps distinguish expected adjustments from concerning adverse effects requiring medical attention.

Positive emotional changes frequently reported during treatment include improved mood stability, increased motivation and drive, enhanced sense of wellbeing, and reduced feelings of depression or low mood. Many men describe feeling more emotionally resilient and better able to cope with daily stressors. These improvements often correlate with the correction of hypogonadal symptoms and may begin to emerge within several weeks of initiating therapy, though full benefits typically take several months to manifest.

Potential challenging emotional responses can include increased irritability or impatience, particularly during the adjustment phase when the body adapts to changing hormone levels. Some individuals report feeling more emotionally reactive or experiencing shorter tempers, especially if testosterone levels fluctuate significantly between doses. Anxiety symptoms may occasionally intensify in susceptible individuals, though this is relatively uncommon when therapy is properly managed.

Mood fluctuations related to injection cycles can occur, particularly with shorter-acting testosterone preparations or when doses are widely spaced. Patients may notice emotional peaks shortly after injection, followed by gradual declines as levels drop before the next dose. This "roller-coaster" effect can manifest as periods of increased energy and confidence alternating with irritability or low mood. Long-acting testosterone undecanoate injections (Nebido) typically provide more stable levels after the initial loading phase.

Some patients report changes in emotional expression during treatment, though these experiences vary widely between individuals. The variability in these responses underscores the importance of individualised monitoring and dose adjustment throughout treatment.

Managing Emotional Side Effects of Testosterone Treatment

Effective management of emotional changes during testosterone therapy requires a collaborative approach between patient and healthcare provider, with regular monitoring and appropriate adjustments to optimise both physical and psychological wellbeing.

Optimising treatment regimen forms the foundation of emotional side effect management. Your prescribing clinician may recommend adjusting the dosing frequency to minimise peak-trough fluctuations—for example, switching from fortnightly to weekly injections of shorter-acting preparations, or considering testosterone gels that provide more stable daily testosterone levels. Dose titration may be necessary if levels are supraphysiological, as excessively high testosterone can contribute to irritability and mood instability.

Regular biochemical monitoring should include testosterone levels and safety parameters. UK practice typically involves monitoring at 3–6 months after initiating treatment, then at least annually once stable. This includes checking testosterone levels, full blood count (particularly haematocrit/haemoglobin), and PSA/prostate assessment in men at risk. Oestradiol testing is not routinely performed but may be considered if symptoms suggest excessive conversion of testosterone to oestrogen (e.g., breast tenderness, gynaecomastia).

Lifestyle modifications significantly support emotional stability during hormone therapy:

• Sleep hygiene – Testosterone can affect sleep patterns; maintaining consistent sleep schedules helps regulate mood (note that TRT may worsen untreated severe obstructive sleep apnoea)

• Regular physical activity – Exercise naturally supports emotional wellbeing and helps optimise testosterone's beneficial effects

• Stress management techniques – Mindfulness, meditation, or cognitive behavioural strategies can help manage increased emotional reactivity

• Limiting alcohol consumption – Alcohol can exacerbate mood fluctuations and interfere with testosterone metabolism

Psychological support may prove beneficial, particularly during the adjustment phase. Some patients benefit from brief counselling or cognitive behavioural therapy to develop coping strategies for managing emotional changes. If pre-existing mental health conditions are present, coordination between your endocrinologist or prescribing physician and mental health professionals ensures comprehensive care.

Medication review is essential, as testosterone can interact with certain medications including anticoagulants (e.g., warfarin), antidiabetic medicines, and corticosteroids. Always check with your prescriber or pharmacist about potential interactions.

When to Seek Medical Advice About Mood Changes

Whilst mild emotional adjustments during testosterone therapy are common and often resolve with time or dose modification, certain mood changes warrant prompt medical evaluation to ensure patient safety and treatment optimisation.

Seek urgent medical attention if you experience:

• Severe depression or persistent low mood lasting more than two weeks, particularly if accompanied by loss of interest in previously enjoyed activities

• Suicidal thoughts or self-harm ideation – call 999 or attend A&E if you feel at immediate risk, contact your GP urgently, call NHS 111, or phone the Samaritans (116 123) for 24/7 support

• Uncontrollable anger or aggressive impulses that feel out of character or threaten your safety or that of others

• Severe anxiety or panic attacks that significantly impair daily functioning

• Psychotic symptoms such as paranoia, hallucinations, or delusional thinking (rare but requiring immediate assessment)

Schedule a routine appointment with your prescribing clinician if you notice:

• Persistent irritability or mood swings that affect relationships or work performance

• Emotional changes that worsen rather than improve after the first 2–3 months of treatment

• Significant mood fluctuations that correlate with your injection schedule

• New-onset anxiety that wasn't present before starting testosterone therapy

• Feeling disconnected from your usual emotional responses

• Sleep disturbances accompanied by mood changes

Before your appointment, keep a mood diary documenting emotional symptoms, their timing relative to testosterone doses, and any triggering factors. This information helps your clinician identify patterns and determine whether treatment adjustment is needed.

Your healthcare provider will assess whether emotional changes relate to testosterone therapy, underlying hypogonadism, or other factors. They may order blood tests to check hormone levels, review your dosing regimen, and consider whether referral to mental health services or endocrinology specialists is appropriate.

If you suspect your mood changes are a side effect of testosterone treatment, you can report this through the MHRA Yellow Card Scheme (yellowcard.mhra.gov.uk). Remember that testosterone therapy should enhance quality of life—persistent emotional difficulties suggest the need for treatment optimisation rather than simply continuing unchanged.

Frequently Asked Questions