Ixekizumab, sold under the brand name Taltz, is an injectable biologic medication used to treat moderate-to-severe plaque psoriasis in adults and children who may need systemic therapy or phototherapy. It works by blocking interleukin-17A, an inflammatory protein involved in the immune response that drives psoriasis. Ixekizumab may be a good option for people with widespread, stubborn, or severe psoriasis that has not improved enough with topical treatments or light therapy. It is given as a subcutaneous injection, with more frequent dosing at the beginning followed by maintenance dosing over time. Because it affects the immune system, clinicians may screen for infections such as tuberculosis before starting treatment. Possible side effects include injection-site reactions, upper respiratory infections, nausea, fungal infections, and possible worsening of inflammatory bowel disease.