Testosterone can be administered parenterally , but it has more irregular prolonged absorption time and greater activity in muscle in enanthate , undecanoate , or cypionate ester form. These derivatives are hydrolyzed to release free testosterone at the site of injection; absorption rate (and thus injection schedule) varies among different esters, but medical injections are normally done anywhere between semi-weekly to once every 12 weeks. A more frequent schedule may be desirable in order to maintain a more constant level of hormone in the system.  Injectable steroids are typically administered into the muscle, not into the vein, to avoid sudden changes in the amount of the drug in the bloodstream. In addition, because estered testosterone is dissolved in oil, intravenous injection has the potential to cause a dangerous embolism (clot) in the bloodstream.
Five randomized clinical trials (including mainly men with alcoholic hepatitis and/or cirrhosis) were identified. Only one trial was assessed as adequate regarding all methodological quality components. Anabolic-androgenic steroids versus placebos or no intervention demonstrated no significant effects on mortality (relative risk [RR] = , 95% CI = -), liver-related mortality (RR = , 95% CI = -), complications to the liver disease (RR = , 95% CI = -), liver histology, and a number of other outcome measures. Anabolic-androgenic steroids were not associated with a significantly increased risk of nonserious adverse events, but with the seldom occurrence of serious adverse events (RR = ,95% CI = -).