Hereditary angioedema is an inherited autosomal dominant disease, i.e., the offspring of patients have a 50% chance of inheriting the disorder. However, in a quarter of patients, the family history is negative, and we encounter "de novo" mutations. The main mediator of edema in HAE patients is bradykinin, so this angioedema does not respond to classical anti-shock therapy as allergic histamine-mediated angioedema does. The accumulation of bradykinin occurs due to a deficiency or dysfunction of C1 inhibitors, serine proteases involved in several cascading systems of our body. The most common is HAE type 1, in 85% of patients, which is characterized by a lack of C1 inhibitors, and is caused by large duplications or deletions, small insertions or deletions and changes of only one base within the SERPING1 gene that causes C1 inhibitor; while HAE type 2, in 15% of patients, is caused by point mutations of reactive loop within its genes that result in the development of nonfunctional C1 inhibitors. However, twenty years ago, HAE type 3 was detected with normal levels of C1 inhibitors resulting from mutations in genes involved in bradykinin metabolism (Hegeman’s factor, plasminogen, and others). New mutations that cause type 3 HAE are discovered on a daily basis and awareness about hereditary angioedema being a severe and debilitating disease is rising, therefore the exact prevalence of the disease is unknown. The edema that occurs most often affects the skin, gastrointestinal and upper respiratory tract , but other solid organs can also be affected. One of the manifestations of HAE is laryngeal edema or edema of the tongue that obstructs the airway and can consequently result in a fatal outcome, if not responded to in time and with adequate therapy. Although not life-threatening, attacks affecting the extremities and abdominal organs are extremely painful and limit patients in their daily activities and are the cause of high absenteeism from work or school. Since attacks of hereditary angioedema are handicapped for patients or potentially life-threatening as they significantly affect the mental state of patients and their functionality, it is necessary to know how to properly treat or prevent them. Today, there are two concepts of the therapeutic approach: namely the treatment of acute seizures and the prevention of seizures. Preference in therapy is given to newer preparations that have significantly improved quality of life of patients. We hope that further advances in science and technology will enable more accessible diagnostic and genetic testing, as well as more effective drugs for all patients, to optimize therapeutic approaches and symptomatology in these severely ill patients. Support and advice on treatment and experiences with other patients can be shared within associations such as HAE Croatia and HAE international. In order to accelerate the path from diagnosis to the application of adequate therapy, it is necessary to continuously work on educating medical professionals.