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.
For the purpose of estrogenic side effect protection during anabolic steroid use, 10-20mg per day is common. If 20mg per day does not protect you from gynecomastia you will need an AI. If you cannot control water retention with this dose you may also need to consider an AI, but with a sound diet that is not overabundant in calories, especially carbohydrates, water retention should be controlled. Many performance athletes often inaccurately blame the steroids for their tremendous water retention, when in truth a lot of the time they’re eating more than they need. Overeating will cause you to hold water, add in aromatizing steroids and this will be worse. Control your diet and control estrogen through SERM’s and most should be fine. If an AI is needed and in heavy cycles and contest cycles they normally are, controlling cholesterol will become even more important.
• Those taking anabolic steroids over an extended period can suffer from infertility, undergo hormonal changes, suffer from psychological defects, risk organ damage , and face the risk of liver cancer
• The law prohibits the possession and usage of any make of anabolic steroid, and you could get arrested for possessing it (forget the claims posted in online shops stating that such steroids are legal )
• An increase risk of Hepatitis (both B & C)
• Facing the embarrassment of having enlarged breasts
• Increased growth of hair in the chest and back of the body
• Risks of an aggressive personality along with depression and aggression
• Damage to the veins
• Facing the risk of being suspended from games and tournaments in the case a urine test is carried out, as it will contain traces of anabolic steroid prohormone even months after you have stopped taking it