Europe — EMA
Nebido (Testosterone Undecanoate)
GNH USA supplies Nebido (testosterone undecanoate), an androgen; anabolic steroid for male hypogonadism and testosterone deficiency. Request supply.
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What is Testosterone Undecanoate?
Testosterone undecanoate, the active ingredient in Nebido, is an androgen; anabolic steroid presented as a 1000 mg/4 mL (250 mg/mL) intramuscular injection solution for intramuscular use. It treats male hypogonadism, testosterone deficiency and delayed puberty in males.
GNH USA supplies Nebido as a licensed, GDP-compliant international pharmaceutical supplier serving hospitals, pharmacies and clinics worldwide.
What is Testosterone Undecanoate used for?
Nebido (testosterone undecanoate) is used in androgen replacement therapy to restore physiological testosterone levels.
- Male hypogonadism: restores normal testosterone concentrations, improving libido, energy and muscle mass. - Testosterone deficiency: normalizes serum testosterone, supporting mood, bone health and erythropoiesis. - Delayed puberty in males: provides exogenous testosterone to initiate and sustain pubertal development.
What are the side effects of Testosterone Undecanoate?
Nebido may be associated with a range of adverse reactions, which are generally categorized by frequency and severity.
Common Side Effects: - Injection site pain: mild to moderate discomfort at the injection site. - Acne: increased sebaceous gland activity leading to pimples. - Fluid retention: mild edema, especially in lower extremities. - Increased hematocrit: rise in red blood cell count, potentially causing thicker blood.
Serious or Rare Side Effects: - Polycythemia: excessive increase in red blood cells that may raise thrombotic risk. - Cardiovascular events: rare occurrences of myocardial infarction or stroke. - Hepatotoxicity: very rare liver enzyme elevations.
What precautions apply to Testosterone Undecanoate?
Before initiating Nebido, clinicians should assess individual risk factors and monitor patients regularly. - Cardiovascular assessment: evaluate history of heart disease before starting therapy. - Hematocrit monitoring: check blood counts periodically to detect polycythemia. - Prostate evaluation: screen for prostate cancer or benign prostatic hyperplasia prior to treatment. - Sleep apnea screening: assess for sleep‑disordered breathing as testosterone may worsen it. - Store at 2-8°C: keep refrigerated, protect from light, do not freeze or shake.
What does Testosterone Undecanoate interact with?
Nebido can interact with several medicines; interactions are grouped by clinical significance.
Major Interactions (Avoid): - Anticoagulants (e.g., warfarin): testosterone‑induced erythropoiesis may increase clot risk. - Insulin or oral hypoglycemics: testosterone may affect glucose metabolism, requiring dose adjustments. - Corticosteroids: concurrent use may exacerbate fluid retention.
Moderate Interactions (Monitor Closely): - CYP3A4 inhibitors (e.g., ketoconazole): may reduce metabolism of testosterone undecanoate, raising serum levels. - GnRH analogues: may blunt the intended androgenic effect. - 5α‑reductase inhibitors (e.g., finasteride): may alter conversion to dihydrotestosterone, affecting efficacy.



