Depo-Testosterone is a prescription hormone replacement medication. It contains the male sex hormone testosterone, and it replaces the testosterone that's usually made naturally by men's bodies. Depo-Testosterone is used to treat symptoms of hypogonadism, a condition in which the body doesn't make enough testosterone on its own. Depo-Testosterone is taken by an injection given by a healthcare professional in a hospital or clinic. It is long lasting (two to four weeks) intramuscular injection made of testosterone cypionate in cottonseed oil. To be effective, Depo-Testosterone must be taken regularly, exactly as directed by your doctor. Don't miss any scheduled appointments for Depo-Testosterone injections. Talk to your doctor to determine whether Depo-Testosterone is right for you.