Determining the correct Testogel dose is essential for safe and effective testosterone replacement therapy in men with confirmed hypogonadism. Testogel, a transdermal testosterone gel licensed in the UK, is available in two formulations with different starting doses and application requirements. The standard initial dose is 50 mg daily for Testogel 1% or 40.5 mg daily for Testogel 16.2 mg/g, applied once each morning to clean, dry skin. Dose adjustments must be guided by blood testosterone measurements and clinical response, under specialist supervision. This article explains recommended Testogel dosing, proper application technique, monitoring requirements, and common mistakes to avoid.

What Is Testogel and How Does It Work?

Testogel is a transdermal testosterone replacement therapy (TRT) licensed in the UK for treating male hypogonadism—a condition where the testes produce insufficient testosterone. Available as a clear, colourless gel containing testosterone (as the active ingredient), Testogel is applied directly to the skin. The gel formulation allows testosterone to be absorbed through the skin into the bloodstream, bypassing first-pass hepatic metabolism and providing steady hormone levels throughout the day.

The mechanism of action involves passive diffusion of testosterone across the stratum corneum. Once absorbed, testosterone circulates in the blood, where it binds to androgen receptors in target tissues including muscle, bone, and the central nervous system. This restores physiological testosterone levels, alleviating symptoms such as reduced libido, fatigue, loss of muscle mass, mood disturbances, and decreased bone density. Testogel is available in different formulations: Testogel 1% (50 mg/5 g) in sachets or pump dispensers, and Testogel 16.2 mg/g in sachets or pump dispensers.

In the UK, Testogel is a prescription-only medicine (POM) regulated by the Medicines and Healthcare products Regulatory Agency (MHRA). It should only be used following confirmed biochemical hypogonadism—typically defined as consistently low serum testosterone levels measured on two separate early-morning occasions, accompanied by clinical symptoms. Laboratory reference ranges vary, so results should be interpreted in the clinical context. Treatment should be initiated and monitored by specialists or clinicians experienced in managing hypogonadism, with regular follow-up to assess efficacy and safety.

Testogel is contraindicated in men with known or suspected prostate cancer or male breast cancer. It is not indicated for performance enhancement, bodybuilding, or age-related testosterone decline without confirmed hypogonadism.

Standard Testogel Dosage Guidelines

The initial recommended dose of Testogel varies by formulation:

• Testogel 1% (50 mg/5 g): The standard starting dose is 50 mg testosterone daily, which equals one 5 g sachet or four pump actuations (each pump actuation delivers 1.25 g gel containing 12.5 mg testosterone)

• Testogel 16.2 mg/g: The standard starting dose is 40.5 mg testosterone daily, which equals one 2.5 g sachet or two pump actuations (each pump actuation delivers 1.25 g gel containing 20.25 mg testosterone)

Testogel should be applied once daily at approximately the same time each morning. The morning application timing aligns with the body's natural circadian rhythm of testosterone production.

Your prescriber will determine the appropriate starting dose based on your baseline testosterone levels, symptom severity, and individual response. It is crucial to follow the prescribed dose exactly as directed—never adjust your dose without medical supervision. Using more gel than prescribed does not accelerate symptom improvement and significantly increases the risk of adverse effects, including polycythaemia (elevated red blood cell count), prostate complications, and cardiovascular concerns.

The maximum recommended daily dose varies by formulation:

• Testogel 1%: Maximum 100 mg testosterone daily (two 5 g sachets or eight pump actuations)

• Testogel 16.2 mg/g: Maximum approximately 81 mg testosterone daily (two 2.5 g sachets or four pump actuations)

Dose adjustments should be based on clinical response and serum testosterone measurements. According to the product information, an initial assessment should occur approximately 14 days after starting treatment, with further monitoring at 3-6 months and then annually. Patients should attend all monitoring appointments to ensure optimal dosing and safety.

How to Apply Testogel Correctly

Proper application technique is essential to ensure optimal testosterone absorption and minimise the risk of transferring the medication to others. Application sites and instructions vary by formulation:

Testogel 1% (50 mg/5 g):

• Apply to clean, dry, intact skin on the shoulders, upper arms, or abdomen

• Avoid washing, showering, or swimming for at least 6 hours after application

Testogel 16.2 mg/g:

• Apply to clean, dry, intact skin on the shoulders or upper arms only (not the abdomen)

• Avoid washing, showering, or swimming for at least 2 hours after application

For both formulations, never apply to the genital area, as this increases the risk of local irritation and erratic absorption.

Step-by-step application instructions:

• Wash and dry your hands thoroughly before opening the sachet or using the pump dispenser

• Apply the gel to the designated area, spreading it thinly and evenly over a large surface area

• Allow the gel to dry completely for at least 3–5 minutes before dressing—do not cover the area until fully dry

• Wash your hands thoroughly with soap and water immediately after application to prevent accidental transfer

• Cover the application site with clothing once dry, particularly if you will have close physical contact with others

Important safety precautions:

• The gel is flammable until dry—avoid naked flames, smoking, or sources of ignition until completely dry

• Prevent skin-to-skin contact with others, especially women and children, as testosterone can transfer through direct contact and may cause virilisation in women or premature sexual development in children

• If accidental contact occurs, the affected person should wash the area immediately with soap and water

• Bed linen and clothing that come into contact with application sites should be washed regularly

Adjusting Your Testogel Dose Based on Blood Tests

Dose titration of Testogel should always be guided by serial blood testosterone measurements combined with clinical assessment of symptom response. The goal is to achieve testosterone levels within the normal physiological range for adult males (as defined by your laboratory's reference range) whilst alleviating hypogonadal symptoms.

According to product information, serum testosterone should be measured approximately 14 days after starting treatment or adjusting the dose. Blood samples should be taken in the morning before gel application (trough levels) to assess steady-state concentrations. Further monitoring is typically performed at 3-6 months and then annually.

Dose adjustments vary by formulation:

Testogel 1% (50 mg/5 g):

• Dose can be adjusted in 2.5 g gel increments (25 mg testosterone)

• For example, from 5 g (50 mg) to 7.5 g (75 mg) to 10 g (100 mg)

Testogel 16.2 mg/g:

• Dose can be adjusted by one pump actuation (20.25 mg testosterone)

• For example, from 2 actuations (40.5 mg) to 3 actuations (60.75 mg)

Regular monitoring is essential throughout treatment and typically includes:

• Serum testosterone levels: Measured as described above

• Full blood count: To detect polycythaemia (haematocrit >0.54), which requires dose reduction or discontinuation

• Prostate-specific antigen (PSA): Baseline and periodic monitoring in men over 40 or those at increased prostate cancer risk; significant PSA rises (e.g., >1.4 ng/mL in 12 months) or abnormal digital rectal examination findings warrant urological assessment

• Liver function tests: Particularly in patients with pre-existing hepatic conditions

• Lipid profile and cardiovascular risk assessment: As testosterone may affect lipid metabolism

Patients should never self-adjust their Testogel dose without medical guidance. If you feel your symptoms are not adequately controlled, contact your GP or specialist rather than increasing the dose independently. If you experience side effects, report them to your doctor and consider using the MHRA Yellow Card scheme (yellowcard.mhra.gov.uk).

Common Mistakes When Using Testogel

Several application errors can compromise treatment efficacy or increase safety risks. One frequent mistake is applying too much gel, either by misunderstanding dosing instructions or attempting to accelerate symptom improvement. Using more than the prescribed amount does not enhance benefits but significantly increases the risk of adverse effects including polycythaemia, sleep apnoea exacerbation, prostate enlargement, and cardiovascular complications. Always measure doses carefully using the sachet or pump as directed.

Inconsistent application timing is another common error. Testosterone levels can fluctuate if the gel is applied at varying times each day, potentially affecting symptom control and making blood test interpretation difficult. Establishing a consistent morning routine—such as applying Testogel after showering—helps maintain steady hormone levels and improves adherence. Missing doses occasionally is less problematic than erratic timing, but if you forget a dose, apply it as soon as you remember on the same day; never double the dose the following day.

Formulation-specific mistakes include applying Testogel 16.2 mg/g to the abdomen (only shoulders and upper arms are approved sites) or washing too soon after application. Remember that Testogel 1% requires at least 6 hours before washing, while Testogel 16.2 mg/g requires at least 2 hours. Many patients underestimate the importance of allowing the gel to dry completely (3–5 minutes minimum).

Ignoring flammability warnings is a serious safety concern. The gel is flammable until completely dry, so avoid naked flames, smoking, or sources of ignition during application and drying.

Failure to prevent transfer to others represents another significant risk. Some patients neglect to wash their hands thoroughly after application or fail to cover application sites with clothing when in close contact with partners or children. This can result in unintended testosterone exposure. If your partner or child develops unexpected symptoms such as acne, increased body hair, or behavioural changes, seek medical advice promptly and review your application technique with your healthcare provider. Always refer to your specific product's Patient Information Leaflet for complete instructions.

Frequently Asked Questions