An EpiPen is an auto-injector that contains epinephrine, a medication that can help decrease the bodys allergic reaction by relaxing the muscles in the airways to make breathing easier, helping to reverse the rapid and dangerous decrease in blood pressure, and relaxing the muscles in the stomach, intestines, and bladder. Epinephrine is a sympathomimetic catecholamine that acts on the whole body to block the progression of the allergic response. It constricts the blood vessels, leading to increased blood pressure and decreased swelling. This allows the muscles around the airways to relax, causing the lungs to open. Epinephrine also prevents the release of more allergic chemicals, which stops the progression of the allergic response.

Each EpiPen Jr Auto-Injector delivers a single dose of 0.15 mg epinephrine injection, USP, 1:2000 (0.3 mL) in a sterile solution. The EpiPen and EpiPen Jr Auto-Injectors are single-use injectable devices that deliver a fixed dose of epinephrine. The pH range is 2.2-5.0. Each 0.3 mL in the EpiPen Jr Auto-Injector contains 0.15 mg epinephrine, 1.8 mg sodium chloride, 0.5 mg sodium metabisulfite, hydrochloric acid to adjust pH, and Water for Injection.

It is important to note that EpiPen is for emergency treatment only and does not replace seeing a healthcare provider or going to the hospital. EpiPen is available in two formats: EpiPen and EpiPen Jr. Your healthcare provider will decide which dose is appropriate for you.