A herniated or bulging disc occurs whenever the disc protrudes unnaturally from the spine, resulting in pressure on the nerves. It is one of the most common diagnosis among patients with back pain, and may be caused by a number of things including aging, spinal injury, or repetitive, heavy lifting. Among bodybuilders, it can occur whenever an individual lifts too much weight or attempts to maneuver the body into unusual positions while lifting, . twisting. Uneven pressure on the discs over a period of months or years can also cause them to break down and eventually bulge out.
Transdermal patches (adhesive patches placed on the skin) may also be used to deliver a steady dose through the skin and into the bloodstream. Testosterone-containing creams and gels that are applied daily to the skin are also available, but absorption is inefficient (roughly 10%, varying between individuals) and these treatments tend to be more expensive. Individuals who are especially physically active and/or bathe often may not be good candidates, since the medication can be washed off and may take up to six hours to be fully absorbed. There is also the risk that an intimate partner or child may come in contact with the application site and inadvertently dose himself or herself; children and women are highly sensitive to testosterone and can suffer unintended masculinization and health effects, even from small doses. Injection is the most common method used by individuals administering AAS for non-medical purposes.