Epinephrine Auto-Injector Needle Length (Does Height or BMI add Valuable Information in Adults?)

Background: Some overweight and obese adults have an increased risk of subcutaneous injection using epinephrine auto injectors (EAIs). Needle lengths of EAIs vary between brands and lots. Objective: To study if BMI or height adds information to define adults at risk of having intraosseous or subcutaneous injection. Methods: Ninety-nine (99) food allergic adult patients, 32 men and 67 women, 18 – 72 years of age, prescribed EAIs were included. The skin to muscle and skin to bone distances were measured by ultrasonography. The effect of injection on naked skin or through thick clothing was analyzed. High and minimal pressure was applied to the ultrasound probe. Results: Two of three men and 1/5 women with BMI