Prior to approval of Cinryze™ C1 Inhibitor (human), certain anabolic steroids were the only approved agent for prophylaxis in the United States; however, its use is limited by its contraindications and major side effects. Certain anabolic steroids are contraindicated in patients who are pregnant, lactating, or have hepatic, renal or cardiac function impairment. Major side effects of these anabolic steroids include androgenic effects, which are often irreversible, and severe hepatic toxicity10. Other complications of therapy with danazol include myalgias with cramps, headaches, anxiety reactions, transaminase elevations, cholesterol abnormalities, and persistent hematuria.11,12.
The adverse effects profile of anabolic steroids creates a treatment dilemma as poor patient adherence limits potential effectiveness. Other options to prevent HAE attacks include avoidance of angiotensin-converting enzyme (ACE) inhibitors and estrogens, as these drugs have been shown to worsen symptoms. Estrogens are thought to decrease expression of ACE, and ACE inhibition acts synergistically with C1-INH deficiency to increase the plasma levels of bradykinin11.