Allergen Alert is a high-fidelity prototype developed for QUT's Design for Health Innovation unit (DVB305). Building on a prior co-design project proposal, it addresses the challenges faced by Brisbane residents with shellfish allergies, a condition that remains difficult to diagnose due to inconsistent allergen test extracts in Australia. With anaphylaxis cases doubling in the past decade, accurate testing is critical, yet clinics often lack the necessary resources. Allergen Alert helps users locate clinics equipped with the right allergen extracts, ensuring more reliable diagnoses. Designed with a user-centred approach, it bridges a key gap in allergy testing accessibility.