There are also a number of side effects associated with general use of this substance. Most notable, blood pressure can begin to rise as cell volume changes. This can reach the point of headaches and high blood pressure, obviously an unwanted effect. Additionally, flu-like symptoms, aching bones, chills and injection site irritations are also possible. Since athletes are not using this product for a medical condition, a strong incidence of side effects should be an indicator to discontinue using the drug. Clearly one should not wish to compromise their health for an athletic push.
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.