Epinephrine Auto-Injector 0.15 mg Injection Syringe, 2-Pack (Rx)Epinephrine Auto Injector Jr, 0. 15 mg Epinephrine (also called adrenaline) is the first line treatment for life threatening allergic reactions (anaphylaxis). The EpiPen Jr auto injector contains 0. 15 mg epinephrine (1: 2000 solution, 0. 3 mL) for intramuscular use. (A 0. 3 mg dose in 0. 3 mL is sold as the adult EpiPen.) Epinephrine is a potent sympathomimetic (alpha and beta agonist) that reverses anaphylaxis by constricting blood vessels (raising