Testosterone
Testosterone is the primary male sex hormone that plays a crucial role in the development of male reproductive tissues and secondary sexual characteristics. As a medication, it is used in testosterone replacement therapy for men with conditions causing low testosterone levels (hypogonadism), helping to restore normal hormonal levels and alleviate associated symptoms such as fatigue, reduced libido, and muscle loss.
Testosterone replacement therapy for men with clinically low testosterone levels to restore normal hormone function and improve related symptoms.
Key facts at a glance
- ATC
- G03BA03
- RxNorm
- 10379
- Generic
- Testosterone
- Class
- atc-g03b
- Brands
- Fortesta, Aveed, Vogelxo, Natesto, Xyosted, Jatenzo, Androderm, Tlando, Kyzatrex, Synovex H, Androgel, Undecatrex, Azmiro, Testim, Testopel
- Availability
- rx
- Lactation
- unknown
- Routes
- topical, nasal, oral
- Forms
- injection, prefilled syringe, gel, solution, suspension, capsule
- Regions
- US, EU, CN, JP
- Monitoring
- —
This page is for informational purposes only.
Do not use this information to diagnose yourself or to replace a physician's advice. Always consult a qualified healthcare provider before starting, stopping, or changing any medication. If you believe you are experiencing a medical emergency, call your local emergency number immediately.
Used to treat male hypogonadism (primary or secondary) when testosterone deficiency has been confirmed by clinical signs and laboratory testing. May also be used in certain cases of delayed puberty in males and hormone replacement in transgender male patients.
Works by binding to androgen receptors in target tissues, mimicking the action of endogenous testosterone. This helps restore normal testosterone levels, supporting male sexual characteristics, muscle mass, bone density, and overall metabolic function.
Requires a valid prescription. Not for use in women except for specific approved indications. Regular monitoring of testosterone levels, prostate health, and blood counts is essential during treatment. Can cause serious side effects including cardiovascular events and polycythemia. Contraindicated in patients with prostate or breast cancer. Subject to controlled substance regulations in many countries.
Official drug label
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This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 25, 2026. · Read our editorial policy