An EpiPen is a brand-name auto-injector device that delivers a pre-measured dose of epinephrine (adrenaline) to treat severe allergic reactions (anaphylaxis). When someone experiences anaphylaxis—potentially from food allergies (nuts, shellfish), insect stings, medications, or other triggers—their airways can swell shut and blood pressure can drop dangerously. EpiPen provides rapid emergency treatment by injecting epinephrine into the thigh, reversing these life-threatening symptoms until emergency medical care arrives. People with known severe allergies typically carry EpiPens at all times. Many schools and public facilities maintain EpiPens for emergencies. Generic versions are available but "EpiPen" has become the common term. Provincial health coverage for EpiPens varies, and cost concerns have prompted policy debates. Proper use requires training, and injection is followed immediately by calling 911, as effects are temporary.