Dupixent (dupilumab) is an injection that helps treat certain inflammatory conditions. This includes eczema, asthma, and chronic obstructive pulmonary disease (COPD), among others. It's a biologic medication known as an interleukin antagonist that lowers inflammation. Dupixent (dupilumab) comes as prefilled pens and prefilled syringes. It's injected under the skin of the belly or thighs (or in the back of the upper arm with someone's help). The dosing schedule depends on the condition you have, your age, and your weight. It's injected either every week, every 2 weeks, or every 4 weeks. Side effects include injection site reactions and eye problems.