Many men using Testogel (testosterone gel) for hypogonadism notice changes in erectile function as treatment progresses. Experiencing erections whilst on Testogel is not only normal but often indicates that the therapy is working effectively to restore testosterone levels. This article explains why erections occur during testosterone replacement, what to expect as your hormone levels normalise, when changes might signal a problem requiring medical attention, and how to manage sexual side effects. Understanding these responses helps you recognise the signs of successful treatment and know when to seek advice from your GP or specialist.

How Testogel Affects Testosterone Levels and Sexual Function

Testogel (testosterone gel) is a hormone replacement therapy licensed in the UK for treating male hypogonadism—a condition where the body produces insufficient testosterone. The gel is applied topically to the skin, with application sites varying by formulation. Testogel 16.2 mg/g pump should only be applied to the shoulders and upper arms, while the 50 mg/5g sachets may be applied to shoulders, upper arms, and in some cases the abdomen (check your specific product information). Testosterone is absorbed through the skin into the bloodstream, supplementing the body's natural levels and aiming to restore them to within the normal physiological range.

Testosterone plays a crucial role in male sexual function, influencing libido (sex drive), erectile function, and overall sexual satisfaction. When testosterone levels are low, men often experience reduced sexual desire, difficulty achieving or maintaining erections, and diminished sexual performance. By restoring testosterone to normal levels, Testogel can improve these symptoms significantly. The medication works gradually, with most men noticing improvements in sexual function within 3–6 weeks of starting treatment, though full benefits may take several months.

Key effects on sexual function include:

• Increased libido and sexual interest

• Improved erectile function and rigidity

• Enhanced sexual satisfaction and performance

• Better overall mood and energy, which indirectly support sexual health

It is important to understand that Testogel does not work like medications such as sildenafil (Viagra). It does not cause immediate erections but rather restores the hormonal environment necessary for normal sexual function. The improvements occur as testosterone levels stabilise over time, supporting the body's natural mechanisms for sexual arousal and response.

Never apply Testogel to the genitals or to broken or irritated skin. After application, wash your hands thoroughly and allow the gel to dry completely before dressing. Avoid showering or swimming for at least 2 hours after application (or as directed in your product information).

Is It Normal to Have an Erection on Testogel?

Yes, experiencing erections whilst using Testogel is common and expected as testosterone levels normalise, and in many cases, is a positive sign that the treatment is working effectively. For men who have been experiencing hypogonadism with associated sexual dysfunction, the return of spontaneous erections—including morning erections—often indicates that testosterone levels are being restored to a healthy range.

Many men starting Testogel notice an increase in the frequency of erections, particularly in the first few weeks to months of treatment. This can include spontaneous erections (those occurring without direct sexual stimulation), nocturnal erections during sleep, and improved erectile response during sexual activity. These changes reflect the restoration of normal testosterone-dependent sexual function and are generally considered a therapeutic benefit rather than a side effect.

The Summary of Product Characteristics (SmPC) for Testogel, approved by the MHRA, acknowledges that testosterone replacement can improve erectile function in men with hypogonadism. Clinical studies have demonstrated that men with low testosterone who receive replacement therapy typically experience improvements in erectile function scores and sexual satisfaction.

What to expect:

• Gradual return of morning erections (a sign of healthy testosterone levels)

• Increased frequency of spontaneous erections

• Improved erectile quality during sexual activity

• Enhanced sexual desire accompanying these physical changes

These responses are part of the intended therapeutic effect of Testogel and reflect the medication's success in addressing the underlying hormonal deficiency. Most men find these changes welcome after experiencing the sexual difficulties associated with low testosterone.

It's worth noting that if you have erectile dysfunction from other causes (such as vascular disease, diabetes, or neurological conditions), you may still require additional treatments such as PDE5 inhibitors (e.g., sildenafil) even after testosterone levels normalise.

When Erections May Indicate a Problem with Testogel

Whilst normal erections are expected and beneficial during Testogel treatment, certain patterns may warrant medical attention. Priapism—a prolonged, painful erection lasting more than four hours without sexual stimulation—is a rare but serious adverse effect that can occur with androgen treatments. This constitutes a medical emergency requiring immediate treatment to prevent permanent damage to penile tissue.

Excessively frequent or persistent erections that cause distress or interfere with daily activities may suggest that testosterone levels have risen too high (supraphysiological levels). Whilst Testogel is designed to deliver steady testosterone absorption, individual variation in absorption rates, incorrect dosing, or inadvertent transfer to others can occasionally result in excessive testosterone levels. Signs that testosterone may be too high include:

• Unusually frequent, uncomfortable erections throughout the day

• Mood changes such as increased irritability or aggression

• Acne or oily skin

• Sleep disturbances or worsening of sleep apnoea

• Headaches

• Increased blood pressure

Another consideration is that some men may have underlying erectile dysfunction from causes other than low testosterone, such as cardiovascular disease, diabetes, or psychological factors. If erectile function does not improve despite normalised testosterone levels, or if erections remain problematic in quality or timing, further investigation may be needed.

When to seek urgent medical attention:

• Any erection lasting longer than 4 hours (priapism)

• Painful erections unrelated to sexual activity

• Erections accompanied by chest pain or cardiovascular symptoms

Your GP or endocrinologist can assess whether your testosterone levels are within the target range through blood tests and adjust your Testogel dose accordingly. Regular monitoring should include not only testosterone levels but also haematocrit/haemoglobin (to check for polycythaemia, a potential side effect) and PSA (prostate-specific antigen) to monitor prostate health. NICE guidance recommends monitoring testosterone levels 3–6 months after starting treatment and annually thereafter.

Managing Sexual Side Effects During Testosterone Treatment

Most sexual changes during Testogel treatment are positive, but some men may need time to adjust, particularly if they have experienced low testosterone for an extended period. Open communication with your partner about these changes can help manage expectations and enhance relationship satisfaction during the adjustment period.

If you experience an increase in libido or erectile function that feels overwhelming or causes relationship difficulties, consider these strategies:

Practical management approaches:

• Timing of application: Apply Testogel at a consistent time each day, as recommended. Some men prefer morning application to align with natural testosterone rhythms.

• Dose optimisation: Your doctor may need to adjust your dose. Testosterone replacement aims for levels in the mid-normal range, not the upper limit.

• Lifestyle factors: Regular exercise, stress management, and adequate sleep support healthy sexual function and help your body adjust to normalised hormone levels.

• Relationship communication: Discuss changes with your partner. Couples counselling or psychosexual therapy may be beneficial if relationship dynamics are affected.

It is essential to use Testogel correctly to maintain stable testosterone levels and prevent transfer to others. Apply the gel to clean, dry, intact skin and allow it to dry completely before dressing. Wash your hands thoroughly after application. Cover the application site with clothing once dry. Avoid skin-to-skin contact with others (particularly women and children) at the application site, and wash the area before intimate contact to prevent testosterone transfer, which can cause unwanted effects in others.

Important considerations:

• Testosterone replacement therapy can suppress sperm production and may impair fertility. If you're planning to have children, discuss this with your specialist before starting treatment.

• Testogel may interact with other medications, particularly anticoagulants (like warfarin) and antidiabetic medicines. Always inform healthcare professionals about all medications you're taking.

If sexual side effects persist or cause significant distress, your healthcare provider may consider alternative testosterone formulations (such as injections or other gel preparations) that provide different pharmacokinetic profiles. Never adjust your Testogel dose without medical supervision, as this can lead to suboptimal treatment or adverse effects.

When to Speak to Your GP About Testogel and Erections

Regular monitoring is an essential component of safe testosterone replacement therapy. NICE Clinical Knowledge Summary guidance recommends that men on testosterone replacement should have their testosterone levels, symptoms, and potential adverse effects reviewed regularly. You should schedule a routine appointment with your GP or specialist if:

• You notice significant changes in erectile function—either improvements or new difficulties

• You experience erections that seem excessive, uncomfortable, or distressing

• Sexual function has not improved after 3–6 months of treatment at an adequate dose

• You develop any new symptoms that concern you

Seek same-day medical advice if you experience:

• An erection lasting longer than 2 hours (seek emergency care if longer than 4 hours)

• Painful erections unrelated to sexual activity

• Chest pain, shortness of breath, or leg swelling (potential cardiovascular concerns)

• Signs of excessive testosterone: severe mood changes, aggressive behaviour, or significant acne

Your GP will typically arrange blood tests to measure your testosterone levels. The timing of these tests should follow the specific guidance in your Testogel product information, as sampling times can vary by formulation. These results help determine whether your dose is appropriate or requires adjustment. The target is generally to achieve testosterone levels in the mid-normal range for your age.

Regular monitoring should also include:

• Haematocrit/haemoglobin (to check for polycythaemia, a potential side effect)

• PSA and prostate assessment (particularly in men over 40)

• Blood pressure and cardiovascular risk assessment

• Blood glucose/diabetes screening if indicated

Questions to discuss with your doctor:

• Are my testosterone levels within the optimal range?

• Is my current dose of Testogel appropriate for my symptoms?

• Could other factors be affecting my sexual function?

• Are there any interactions with my other medications?

Remember that testosterone replacement is a long-term treatment requiring ongoing monitoring. Building a good relationship with your healthcare team and maintaining open communication about sexual health concerns ensures you receive the most effective and safe treatment.

If you experience any suspected side effects from Testogel, you can report them via the MHRA Yellow Card scheme at yellowcard.mhra.gov.uk or through the Yellow Card app.

Frequently Asked Questions