Omalizumab is a humanized monoclonal anti-IgE antibody that is currently FDA-approved for allergic asthma. Given its mechanism of action, recent reports have suggested its possible clinical use for food allergy and some forms of anaphylaxis. Omalizumab exerts its action by binding to circulating IgE, reducing IgE receptor expression, and decreasing mediator release from mast cells and basophils. Clinical trials using omalizumab in patients with food allergy resulted in achieving tolerance to higher amounts of the allergen in some patients. When used as an adjunct therapy during immunotherapy trials in patients with food allergy and anaphylaxis, omalizumab allowed more rapid and higher doses of immunotherapy to be given. Omalizumab has also been reported to be effective in a few patients with idiopathic anaphylaxis and mast cell disorders. Large multi-center trials are needed to confirm the above findings, and to identify subsets of patients that would benefit the most from omalizumab.