Hereditary and acquired angioedema are potentially life-threatening diseases characterized by spontaneous episodes of subcutaneous and submucosal swelling of face, lips, oral cavity, larynx, and GI tract. Hereditary angioedema (HAE) usually presents within the first and second decades of life, whereas acquired angioedema presents in adults after 40 years of age. These clinical symptoms together with reduced C1 inhibitor levels and/or activity can usually confirm the diagnosis. In recent years, multiple novel therapies for treating hereditary angioedema have emerged including C1 inhibitor concentrates, ecallantide/kallikrein inhibitor, and icatibant/bradykinin receptor antagonist. This article reviews the clinical presentation, diagnosis, treatment, and prophylaxis of HAE. Lastly, this article takes into consideration that, in reality, acute care treatment can often be limited by each hospital’s formulary, included is a review of HAE treatments available at the nine major hospitals in Rhode Island. [Full article available at http://rimed.org/rimedicaljournal-2016-06.asp, free with no login].