Icatibant, which is typically injected under the skin, is a medication used to treat “attacks of hereditary angioedema (an immune system disorder) in adults”. Bear in mind that it does not cure this condition. According to webmd.com, Icatibant works by “blocking the action of a natural substance in the body called bradykinin. Bradykinin is thought to cause the symptoms of a hereditary angioedema attack”. Remember to tell your doctor if you have any allergies whatsoever, or if you’re pregnant or breastfeeding before using Icatibant so as to make sure that it will be safe, not to mention effective. As for the side effects of this medication, they include headache, drowsiness, fever, and numbness.