Sustanon 250 contains, per mL, short-acting testosterone propionate, 60 mg of testosterone phenylpropionate, 60 mg of testosterone isocaproate, and 100 mg of testosterone decanoate. The first, testosterone propionate, is short-acting and gives Sustanon a quick onset of action in a steroid cycle. The other esters are medium to long-acting.
This product has the effect of heavy aromatizing therefore the main side effect will be that testosterone will be converted into estrogen. This increase in the levels of estrogen will lead to problems like the development of breast among males and extensive water retention. This might result in high blood pressure.