Testogel sachets provide transdermal testosterone replacement therapy for men with clinically confirmed hypogonadism. Each sachet contains 50 mg of testosterone in a gel formulation, applied once daily to the shoulders, upper arms, or abdomen. Correct application technique is essential to ensure optimal hormone absorption whilst preventing accidental transfer to partners or children. This guide explains how to use Testogel sachets safely and effectively, covering application methods, timing, dosage adjustments, and important precautions. Regular monitoring through blood tests and clinical review ensures treatment remains safe and appropriate for your individual needs.

What Is Testogel and When Is It Prescribed?

Testogel is a transdermal testosterone replacement therapy (TRT) available as a clear, colourless gel containing testosterone as the active ingredient. Each sachet typically contains 50 mg of testosterone in 5 g of gel, designed for once-daily application to the skin. The gel is formulated to deliver a controlled dose of testosterone through the skin into the bloodstream, providing physiological levels of this essential hormone.

Testogel is prescribed for testosterone replacement in adult men with hypogonadism—a condition where the testes produce insufficient testosterone. This may be primary hypogonadism (testicular failure) or secondary hypogonadism (pituitary or hypothalamic dysfunction). Symptoms of testosterone deficiency include reduced libido, erectile dysfunction, fatigue, loss of muscle mass, increased body fat, mood disturbances, and decreased bone density. Diagnosis requires both clinical symptoms and biochemical confirmation through blood tests showing consistently low serum testosterone levels, typically measured on two separate mornings (between 07:00-11:00), with fasting samples if feasible.

Before prescribing, clinicians must exclude contraindications such as known or suspected prostate or breast cancer, severe cardiac or hepatic disease, and assess cardiovascular risk factors. Testogel provides an alternative to injectable testosterone, with daily application allowing relatively easy dose adjustment, though it requires precautions to prevent transfer to others through skin contact. It's important to note that testosterone replacement therapy can suppress sperm production and is not suitable for men trying to conceive.

How to Apply Testogel Sachets Correctly

Correct application technique is essential to ensure optimal testosterone absorption whilst minimising the risk of transfer to others. Before application, ensure the skin is clean, dry, and intact—avoid applying to broken, irritated, or recently shaved skin. The recommended application sites are the shoulders, upper arms, or abdomen. Do not apply Testogel to the genital area, as this increases the risk of local irritation and transfer to partners.

Step-by-step application process:

• Open the sachet by tearing along the notch at the top

• Squeeze the entire contents onto one palm

• Apply the gel thinly and evenly across the chosen area using both hands

• Spread over a surface area roughly the size of two palms

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

• Wash your hands thoroughly with soap and water immediately after application

Important precautions include covering the application site with clothing once the gel has dried, particularly before any situation involving close skin contact with others. Avoid washing, showering or swimming for at least 2 hours after application to ensure adequate absorption. The gel contains alcohol, so avoid flames, smoking or open heat sources until the application site is fully dry.

To prevent testosterone transfer to partners or children, ensure the application site is covered or wash the area thoroughly with soap and water before any direct skin-to-skin contact. Children and women, particularly those who are pregnant, should avoid contact with application sites. If accidental contact occurs, the affected person should wash the area immediately with soap and water. These precautions are crucial as testosterone transfer can cause virilisation in women and children, including unwanted hair growth and other androgenic effects.

Common Side Effects and When to Seek Help

Like all medications, Testogel can cause side effects, though not everyone experiences them. Common local reactions at the application site include skin irritation, redness, itching, or dryness, affecting up to 1 in 10 users. These are usually mild and often resolve with continued use. Rotating application sites can help minimise local reactions. Acne or oily skin may develop or worsen, reflecting testosterone's androgenic effects on sebaceous glands.

Systemic side effects may include headache, mood changes (including increased aggression or irritability), hot flushes, and changes in libido. Some men experience gynaecomastia (breast enlargement or tenderness), which occurs due to peripheral conversion of testosterone to oestradiol. Weight gain, fluid retention, and increased red blood cell production (polycythaemia) can occur, the latter requiring monitoring through regular blood tests. Sleep disturbances, including sleep apnoea, may develop or worsen in susceptible individuals. Lower urinary tract symptoms or benign prostatic hyperplasia (BPH) may also worsen in some men.

Seek urgent medical attention if you experience:

• Signs of allergic reaction: rash, swelling of face or throat, difficulty breathing

• Chest pain, shortness of breath, or signs of blood clots (leg pain, swelling, warmth)

• Prolonged or painful erections lasting more than 4 hours (priapism)

• Signs of liver problems: yellowing of skin or eyes, dark urine, severe abdominal pain

• Sudden severe headache, vision changes, or weakness on one side of the body

Contact your GP if you notice mood changes, depression, increased aggression, breast lumps, difficulty urinating, ankle swelling, or if side effects become troublesome. Regular monitoring is essential—your doctor will arrange blood tests to check testosterone levels, full blood count, prostate-specific antigen (PSA), liver function, and lipid profile as clinically indicated. Report any suspected side effects via the MHRA Yellow Card scheme.

When to Apply and Dosage Guidelines

Timing of application should be consistent to maintain steady testosterone levels. Most men apply Testogel in the morning, which mimics the natural circadian rhythm of testosterone production. However, the specific time is less critical than consistency—choose a time that fits your daily routine and apply at approximately the same time each day. Morning application is often preferred as it allows the gel to dry before bedtime, reducing the risk of transfer to partners during sleep.

Standard dosing typically begins with one 50 mg sachet (5 g of gel) applied once daily. Your doctor will assess your response through symptom improvement and blood testosterone levels measured 2–4 hours after application (or as per local protocol), typically 2–4 weeks after starting treatment. Based on these results, the dose may be adjusted:

• Maintenance dose range: 50–100 mg daily (1–2 sachets)

• Dose adjustments are made in 25 mg increments based on clinical response and testosterone levels

• If 25 mg increments are needed, your doctor may prescribe 25 mg sachets if available, or consider alternative formulations such as the pump

• Do not store opened sachets for later use

• The maximum recommended dose is usually 100 mg daily

If you miss a dose, apply it as soon as you remember on the same day. If it is almost time for your next dose, skip the missed dose and continue with your regular schedule. Do not apply a double dose to make up for a forgotten application. Consistent daily use is important for maintaining stable testosterone levels and optimal symptom control.

Long-term monitoring is essential for safe TRT use. Your GP or endocrinologist will arrange regular reviews, typically every 3 months initially, then 6–12 monthly once stable. Monitoring includes assessment of symptoms, physical examination (including prostate examination), and blood tests for testosterone levels, haematocrit, PSA, liver function, and lipid profile. Baseline PSA and digital rectal examination are recommended before starting treatment, with ongoing monitoring throughout therapy. Treatment should be reviewed if PSA rises significantly or if concerning symptoms develop.

Frequently Asked Questions