Anabolic steroids and fibrinolysis.

Anabolic steroids increase the activity of the fibrinolytic system by reducing plasma levels of inhibitors (plasminogen activator inhibitor type I, histidine-rich glycoprotein, alpha-2-macroglobulin) and increasing plasma levels of tissue-type plasminogen activator activity, plasminogen, and plasmin activity (B beta 15-42 fragment of fibrinogen). Plasminogen activator inhibitor levels are elevated, and tissue-type plasminogen activator activity is depressed, in a variety of disease states, including premature venous or arterial thrombosis, connective tissue disorders, and cancer. Such abnormalities can be reversed by anabolic steroids. However the clinical benefits and adverse effects of such treatment remain to be established by large, randomized controlled trials.