Testogel® / Testogel® Dosiergel

Testogel® is a clear gel for external use that contains the active ingredient testosterone. It is used in adult men as hormone replacement therapy when the body does not produce enough testosterone (male hypogonadism).

Testosterone deficiency can manifest as fatigue, reduced libido, erectile dysfunction, mood swings, muscle wasting, and osteoporosis. Testogel® is applied to the skin once daily and releases testosterone evenly throughout the day. It is available as Testogel® (50 mg sachet) and as Testogel® Dosiergel (pump dispenser with 16.2 mg testosterone per gram of gel, 20.25 mg per actuation).

Mechanism of action:

• Testosterone is absorbed through the skin (transdermally)
• Enters the bloodstream and restores physiological testosterone levels
• Acts on androgen receptors in numerous tissues

Effects of testosterone:

• Increase in libido and sexual function
• Building and maintaining muscle mass
• Strengthening of bone density
• Improvement of mood and energy
• Promotion of red blood cell production
• Influence on fat and glucose metabolism

Pharmacokinetics: After application to the skin, testosterone is absorbed continuously. Stable blood levels are reached after 2–3 days of regular use. The full clinical effect occurs after a few weeks.

Testogel® is suitable for:

• Adult men with confirmed testosterone deficiency (hypogonadism)
• Confirmed by clinical symptoms AND low testosterone levels in the blood (at least two morning measurements)

Not suitable:

• Women (Testogel® is approved only for men)
• Prostate cancer or suspected prostate cancer
• Breast cancer in men
• Severe liver, heart, or kidney failure
• Men who wish to father children (testosterone inhibits spermatogenesis)
• Polycythemia (hematocrit > 54%)

Testogel® sachets:

• Starting dose: 50 mg (1 sachet) daily
• Adjustment based on blood level monitoring: 25–100 mg daily

Testogel® Dosiergel (pump dispenser):

• 1 pump actuation = 20.25 mg testosterone
• Starting dose: 2 actuations (40.5 mg) daily
• Adjustment: 1–4 actuations daily depending on blood levels

Monitoring:

• Check testosterone levels after 2–4 weeks
• Target range: testosterone in the mid-normal range (approx. 15–25 nmol/L)
• Monitor hematocrit and PSA regularly

Application:

• Apply once daily in the morning to clean, dry, intact skin
• Preferred sites: upper arms, shoulders, or abdomen
• Spread the gel evenly in a thin layer
• Allow to dry for at least 3–5 minutes before getting dressed
• Wash hands thoroughly after application

Important notes:

• Do NOT apply to the genital area (severe irritation possible)
• Avoid skin contact with your female partner or with children (testosterone transfer!)
• Cover the application site with clothing or wash it before contact
• Do not apply to irritated or inflamed skin
• Always apply at the same time of day

Testogel® must not be used in cases of:

• Prostate cancer or suspected prostate cancer
• Breast cancer in men
• Known hypersensitivity to testosterone
• Polycythemia (hematocrit > 54%)

Caution in cases of:

• Severe heart, liver, or kidney failure or ischemic heart disease (risk of serious complications due to edema with or without heart failure)
• Sleep apnea syndrome
• Benign prostatic enlargement (BPH)
• Epilepsy
• Migraine
• High blood pressure
• Clotting disorders
• Diabetes (blood glucose monitoring recommended)

Wish to have children: Exogenous testosterone suppresses the body's own sperm production and has a contraceptive effect in men. If you wish to have children, other options (e.g., hCG, clomiphene off-label) should be discussed.

Common (1–10%):

• Skin reactions at the application site (redness, itching)
• Acne
• Increased hematocrit/erythrocytosis, polycythemia (increased red blood cells)
• Elevated PSA level
• Headache

Uncommon (0.1–1%):

• Mood swings, irritability
• Gynecomastia (breast enlargement)
• Weight gain
• Hair loss (androgenetic)
• High blood pressure
• Prostate problems

Rare but serious:

• Liver function disorders
• Worsening of sleep apnea

Monitoring: Regular checks of hematocrit, PSA, liver values, and lipid profile are essential.

Interactions:

• Anticoagulants (warfarin, phenprocoumon) → enhanced inhibition of blood clotting, INR monitoring required
• Insulins and oral antidiabetic drugs → enhanced lowering of blood glucose possible
• Corticosteroids → increased tendency toward edema

Enzyme inducers:

• Barbiturates, phenytoin, rifampin → accelerated breakdown of testosterone possible

Important: Concomitant use with other androgenic substances should be avoided.