Testogel is a prescription testosterone replacement therapy gel used to treat male hypogonadism in the UK. Hypogonadism occurs when the testes produce insufficient testosterone, leading to symptoms such as reduced libido, fatigue, and decreased muscle mass. Available as 1% sachets or a pump dispenser, Testogel delivers testosterone through the skin, providing stable hormone levels when applied daily. It is regulated by the MHRA and requires proper diagnosis with blood tests and medical supervision. This article explains how Testogel works, who can use it, application techniques, side effects, and how to obtain it through the NHS or private healthcare.

What Is Testogel and How Does It Work?

Testogel is a transdermal testosterone replacement therapy (TRT) gel licensed in the UK for treating male hypogonadism—a condition where the testes produce insufficient testosterone. It is available in two formulations: 1% gel sachets (50 mg testosterone per 5 g sachet) and a 16.2 mg/g pump dispenser. Each application delivers a measured dose of testosterone that is absorbed through the skin into the bloodstream.

The mechanism of action involves transdermal absorption of exogenous testosterone, which supplements or replaces endogenous production. Once absorbed, testosterone binds to androgen receptors throughout the body, influencing multiple physiological processes including muscle mass maintenance, bone density, libido, mood regulation, and secondary sexual characteristics. The gel formulation provides relatively stable serum testosterone levels with fewer peaks and troughs than some injectable alternatives when applied daily.

Testogel is manufactured by Besins Healthcare and is regulated by the Medicines and Healthcare products Regulatory Agency (MHRA) in the UK. The gel dries quickly after application, forming a reservoir in the skin from which testosterone is gradually released into circulation. Important safety note: Testogel is alcohol-based and flammable—avoid open flames, smoking, or sources of ignition until the gel has completely dried.

Testogel is a prescription-only medicine (POM) and should only be used under medical supervision following confirmed biochemical hypogonadism with appropriate symptoms. It is not indicated for performance enhancement, bodybuilding, or age-related testosterone decline without confirmed pathological hypogonadism. According to the Summary of Product Characteristics (SmPC) available via the electronic medicines compendium (emc), proper diagnosis and monitoring are essential for safe use.

Who Can Use Testogel in the UK?

Testogel is indicated for adult males with confirmed hypogonadism resulting from either primary testicular failure or secondary hypothalamic-pituitary dysfunction. Diagnosis requires both biochemical evidence and clinical symptoms such as reduced libido, erectile dysfunction, fatigue, decreased muscle mass, or mood disturbances. According to NICE Clinical Knowledge Summaries (CKS), diagnosis should be based on two separate early-morning (approximately 7–11 am) serum total testosterone measurements showing low levels, accompanied by symptoms. Additional tests including luteinising hormone (LH), follicle-stimulating hormone (FSH), sex hormone-binding globulin (SHBG), and prolactin help determine the cause. If secondary hypogonadism is suspected or prolactin is significantly elevated, pituitary imaging and specialist referral may be required.

Absolute contraindications to Testogel use (as per the UK SmPC) include:

• Known or suspected androgen-dependent carcinoma of the prostate or male breast cancer

• Hypersensitivity to testosterone or any gel excipients

Warnings and precautions requiring careful assessment and monitoring include:

• Pre-existing cardiovascular disease (the MHRA advises caution; evidence on cardiovascular risk remains debated)

• Severe untreated obstructive sleep apnoea (may worsen with testosterone therapy)

• Polycythaemia or elevated haematocrit (testosterone stimulates red blood cell production)

• Conditions predisposing to oedema (e.g., severe heart, liver, or kidney disease)

All men should undergo baseline prostate assessment including digital rectal examination (DRE) and prostate-specific antigen (PSA) testing before commencing therapy, with periodic monitoring tailored to age and risk factors as per the SmPC and British Society for Sexual Medicine (BSSM) guidance. Men with diabetes or obesity require individualised risk-benefit assessment.

Testogel is not licensed for use in women or children. Accidental exposure in these groups can cause virilisation effects. Pregnant women must avoid contact with application sites due to potential harm to the developing foetus. The decision to prescribe Testogel should involve specialist endocrinology or urology input, particularly for younger men where fertility preservation may be relevant, as exogenous testosterone suppresses spermatogenesis through negative feedback on the hypothalamic-pituitary-gonadal axis.

How to Apply Testogel Safely and Effectively

Proper application technique is essential for therapeutic efficacy and safety. Testogel should be applied once daily, preferably at the same time each morning to maintain consistent testosterone levels. Dosing differs between formulations:

For 1% gel sachets:

• Usual starting dose: 50 mg (one 5 g sachet) daily

• Dose may be adjusted in 25 mg increments based on serum testosterone monitoring, up to a maximum of 100 mg daily

For 16.2 mg/g pump:

• Usual starting dose: 40.5 mg (two pump actuations) daily

• Dose may be adjusted in 20.25 mg increments based on monitoring

Application instructions:

• Apply to clean, dry, intact skin on the shoulders and upper arms. For the 1% sachets only, the abdomen may also be used. The 16.2 mg/g pump should be applied to shoulders and upper arms only. Never apply to the genital area.

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

• Squeeze the entire sachet contents or dispense the prescribed number of pump actuations onto the application area and spread thinly in a single layer

• Allow the gel to dry for 3–5 minutes before dressing

• Wash hands thoroughly with soap and water immediately after application

• Flammability warning: The gel is alcohol-based. Avoid open flames, smoking, or sources of ignition until the gel has completely dried.

The application site should not be washed or showered for an appropriate interval after application to ensure adequate absorption: at least 6 hours for 1% sachets and at least 2 hours for the 16.2 mg/g pump (refer to the specific SmPC for your formulation). Swimming or vigorous exercise should be avoided during this period. Rotate application sites within the permitted areas to prevent skin irritation.

Critical safety measures to prevent transfer to others (particularly women and children):

• Cover the application site with clothing once the gel has dried

• If physical contact is anticipated before the minimum wash-off time, wash the application area thoroughly with soap and water or ensure it is covered with a garment

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

• Do not share towels or clothing that may have contacted application sites

If a dose is missed, apply it as soon as remembered unless it is nearly time for the next dose—never double the dose. Consistent daily application optimises therapeutic benefit and minimises fluctuations in testosterone levels.

Common Side Effects and Safety Considerations

Like all medicines, Testogel can cause side effects, though not everyone experiences them. According to the UK SmPC, common adverse effects include:

• Application site reactions: erythema, irritation, dryness, or rash

• Acne and oily skin (due to androgenic effects on sebaceous glands)

• Headache

• Mood changes: increased aggression, irritability, or mood swings

• Prostate disorders including benign prostatic hyperplasia or increased PSA levels

• Polycythaemia (increased red blood cell production)

Skin reactions at the application site are usually mild and transient. Persistent or severe irritation should prompt review of application technique or consideration of alternative formulations.

Serious but less common risks include cardiovascular events. The MHRA has reviewed the evidence and advises caution in men with pre-existing cardiovascular disease, though the overall evidence on cardiovascular risk remains debated. Obstructive sleep apnoea may worsen with testosterone therapy; patients with symptoms such as loud snoring or daytime somnolence should be evaluated.

Regular monitoring is essential for safe long-term use. According to the SmPC and BSSM/Society for Endocrinology guidance, monitoring should include:

• Testosterone levels: Check during dose titration (e.g., around 3 months after initiation or dose change) and at least annually once stable

• Full blood count and haematocrit: Baseline, then at 3, 6, and 12 months, and annually thereafter. Treatment should be interrupted if haematocrit exceeds 54%, pending evaluation

• PSA and prostate examination (DRE): Baseline and periodic monitoring tailored to age and risk factors (e.g., at 3, 6, 12 months, then annually)

• Lipid profile and liver function tests: As clinically indicated

When to seek medical advice:

• Prolonged or painful erections (priapism)

• Signs of allergic reaction: rash, swelling, breathing difficulty

• Chest pain, leg swelling, or shortness of breath

• Significant mood changes, depression, or increased aggression

• Yellowing of skin or eyes (jaundice)

• Visual disturbances or severe headache (may indicate pituitary pathology)

Patients should report any concerning symptoms to their GP promptly. Women or children accidentally exposed should seek medical advice if virilisation signs develop (e.g., deepening voice, increased body hair, acne).

Reporting side effects: Suspected adverse reactions should be reported via the MHRA Yellow Card Scheme at yellowcard.mhra.gov.uk or by searching for MHRA Yellow Card in the Google Play or Apple App Store.

Getting Testogel: NHS Prescriptions and Private Options

Testogel is available in the UK through NHS prescription following appropriate diagnosis and assessment. Initial diagnosis of hypogonadism typically occurs in primary care. NICE Clinical Knowledge Summaries recommend that men with suspected or confirmed hypogonadism should be referred to a specialist (endocrinology or urology) for further assessment and consideration of treatment initiation, though local shared-care arrangements vary.

The pathway to obtaining Testogel on the NHS generally involves:

• GP consultation with symptom assessment

• Blood tests confirming low testosterone (two separate early-morning samples taken between approximately 7–11 am), plus LH, FSH, SHBG, and prolactin

• Exclusion of secondary causes and assessment for contraindications and warnings

• Specialist referral for treatment initiation and establishment of a monitoring plan

• Ongoing prescribing and monitoring, often shared between specialist and GP according to local protocols

Once stabilised, repeat prescriptions may be issued by GPs with periodic specialist review. NHS prescription charges apply in England; charges are updated annually and current rates are available from NHS Business Services Authority. Prescriptions are free in Scotland, Wales, and Northern Ireland. Exemptions from charges exist for certain groups in England.

Private healthcare options provide an alternative route, with access to specialist consultation and treatment initiation outside NHS waiting times. Private endocrinologists can assess, diagnose, and prescribe Testogel. Private prescriptions can be dispensed at any pharmacy; medication costs vary depending on dose, formulation, and supplier.

Shared care arrangements between private specialists and NHS GPs are sometimes possible, where diagnosis and initiation occur privately but ongoing prescribing transfers to the NHS. This requires GP agreement and appropriate local shared-care protocols.

Patients should be cautious about online prescribing services. Legitimate services require proper medical assessment and should be provided by Care Quality Commission (CQC)-regulated healthcare providers, with prescriptions dispensed by General Pharmaceutical Council (GPhC)-registered pharmacies. The MHRA warns against purchasing medicines from unregulated online sources due to risks of counterfeit or substandard products. Testosterone should never be supplied without adequate clinical evaluation, as this is unsafe and potentially illegal.

Regardless of prescribing route—NHS or private—regular monitoring remains essential for safe, effective treatment.

Frequently Asked Questions