Anaphylaxis is a life-threatening allergic reaction, associated with mental health burden in patients and caregivers. Intramuscular adrenaline via autoinjector (AAI) is the recommended treatment for the management of anaphylaxis in non-hospital settings; however, AAIs are underused. This study aimed to assess parental self-efficacy in managing child's anaphylaxis and administering AAI to understand how to effectively support families. Seventy-five parents of children with severe food allergy completed a questionnaire to measure parental self-efficacy in managing child food-induced anaphylaxis (PSEMA). We conducted an exploratory factor analysis with 12 items, using principal axis factoring as the extraction method. We used Cronbach's alpha to assess the internal consistency of the factors. We used the Anderson-Rubin approach to estimate the factors' scores and provide a kernel density estimate of their distributions. An assessment through linear regression between the total factors' score and total score was performed. A five-factor model was identified. The factors that emerged were conceptually related to "F1. Manage Injection," "F2. Manage AAI Device," "F3. Manage Anaphylaxis," "F4. Manage Emergency," and "F5. Manage Emotions." The questionnaire demonstrated high internal consistency, with a Cronbach's alpha of 0.91 (95% CI: 0.87-0.94) The variation in the total score explained 90% of the variation in the factor score. The PSEMA questionnaire promises to be an easy and effective tool for measuring parents' self-efficacy in managing anaphylaxis and AAI, allowing clinicians to identify gaps in education and provide effective training.