In addition to its medical use, testosterone undecanoate is used to improve physique and performance. The drug is a controlled substance in many countries and so non-medical use is generally illicit. Medical dosage
Testosterone undecanoate is used in androgen replacement therapy. It is specifically approved only for the treatment of hypogonadism. As an intramuscular injection, it is administered at a dosage of 1,000 mg once every 12 weeks. Conversely, oral testosterone undecanoate must be taken two or three times a day with food. Side effects
Side effects of testosterone undecanoate include virilization among others. Anaphylaxis
The Reandron 1000 formulation (Nebido in the United States) contains 1,000 mg of testosterone undecanoate suspended in castor oil with benzyl benzoate for solubilization and as a preservative, and is administered by intramuscular injection. As an excipient in Reandron 1000, benzyl benzoate has been reported as a cause of anaphylaxis (a serious life-threatening allergic reaction) in a case in Australia. Bayer includes this report in information for health professionals and recommends that physicians "should be aware of the potential for serious allergic reactions" to preparations of this type. In Australia, reports to the Adverse Drug Reactions Advisory Committee (ADRAC), which evaluates reports of adverse drug reactions for the Therapeutic Goods Administration (TGA), show several reports of allergic reactions since the anaphylaxis case from 2011. Pharmacology
Pharmacodynamics
Testosterone undecanoate is a prodrug of testosterone and is an androgen and anabolic–androgenic steroid (AAS). That is, it is an agonist of the androgen receptor (AR).
Brand names
Testosterone undecanoate is or has been marketed under a variety of brand names, including Andriol, Androxon, Aveed, Cernos Depot, Jatenzo, Nebido, Nebido-R, Panteston, Reandron 1000, Restandol, Undecanoate 250, and Undestor. Availability
Intramuscular testosterone undecanoate is available in the United States, Canada, Europe, and elsewhere in the world. It is approved in over 100 countries worldwide. Oral testosterone undecanoate is available in Canada, Europe, Mexico, Asia, and in the United States. Intramuscular testosterone undecanoate is marketed most commonly as Nebido in Canada and Europe and as Aveed in the United States while oral testosterone undecanoate is marketed most commonly as Andriol. Legal status
Testosterone undecanoate, along with other AAS, is a schedule III controlled substance in the United States under the Controlled Substances Act and a schedule IV controlled substance in Canada under the Controlled Drugs and Substances Act.In March 2019, the US Food and Drug Administration (FDA) approved testosterone undecanoate (Jatenzo), an oral testosterone capsule to treat men with certain forms of hypogonadism. These men have low testosterone levels due to specific medical conditions, such as genetic disorders like Klinefelter syndrome or tumors that have damaged the pituitary gland. The FDA granted the approval of Jatenzo to Clarus Therapeutics.In March 2022, testosterone undecanoate (Tlando) was approved for medical use in the United States. Research
Non-alcoholic steatohepatitis
In 2013, a phase II clinical trial testing intramuscular testosterone undecanoate for the treatment of non-alcoholic steatohepatitis (NASH) was initiated in the United Kingdom.