To report a case of successful use of a transdermal contraceptive in a patient with hereditary angioedema.Case report.University medical center.A patient who had used oral contraceptives contracted SC and submucosal tumefaction every 1 or 2 months. She was diagnosed with type I hereditary angioedema. It was determined that she was complement C4 deficient and C1-inhibitor quantitative deficient but functional C1-inhibitor normal. After she was diagnosed, the use of oral contraceptives was contraindicated.Oral contraceptives were suspended, and a hormonal transdermal contraceptive was started.The absence of symptoms after 26 months using a transdermal contraceptive.After 26 months of using this treatment, the patient has not experienced any symptoms of the hereditary angioedema.The use of hormonal contraceptives transdermally can be an alternative in patients with hereditary angioedema.