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. 
This injectable is testosterone suspended in water. This drug has been used since the 1940’s, where it was primarily used by Russian athletes and German soldiers. Suspension is still a favorite of athletes who like the immediate effects of the drug. Being water based, it gets in the blood in a matter of hours and has a life of around a day, requiring frequent administration. Many elite bodybuilders have long term suspension habits and many power lifters like the increased aggression from the androgenic properties of suspension. Some athletes take the drug the morning of a contest and claim it makes their muscles look harder and fuller. Testosterone suspension is similar to Anadrol, it can produce major changes in the physique.