Testosterone, like many anabolic steroids, was classified as a controlled substance in 1991. Testosterone is administered parenterally in normal and delayed-release (depot) forms. In September 1995, the FDA approved testosterone transdermal patches (Androderm), and many transdermal forms and brands are now available including implants, gels, and topical solutions. A testosterone buccal system, Striant, was FDA-approved in July 2003; Striant is a mucoadhesive product that adheres to the buccal mucosa and provides a controlled and sustained release of testosterone. In May 2014, the FDA approved an intranasal gel formulation of testosterone (Natesto). A transdermal patch (Intrinsa) for hormone replacement in women is under investigation; the daily dosages used in women are much lower than for products used in males. The FDA refused approval for Intrinsa in 2004 stating that more data regarding safety, especially in relation to cardiovascular and breast health, were required.
Testsosterone implants contain 800 mg of testosterone (usually in the form of four 200 mg pellets). They are implanted into the buttocks or abdomen, and provide testosterone replacement for around six months. Implants are replaced periodically, once symptoms of testosterone deficiency recur. Inserting the testosterone pellets is a minor surgical procedure, requiring local anaesthetic ; this is the major limitation of this method of treatment. However, men using this form of testosterone replacement are usually satisfied with the method, and are more likely to continue being treated than men using other modes of testosterone replacement.