International audienceBy combining the institutional approach and the rational model of digital innovation, there is increasingly a great interest in the implementation of blockchain solutions in healthcare but, until then concrete evidence for this type of project is missing. At the same time the healthcare sector, allergology in particular seems to face security (confidentiality, availability and integrity) issues and information audit trail weaknesses. For these reasons, our study focuses on the co-construction of a distributed ledger for patients allergies with healthcare professionals. The aim is to design and implement a reliable tool to deal with the availability , integrity and confidentiality of information about new allergies and distinguish between validated allergies and declarative allergies for the purpose of mitigating negative effects of unavailability of reliable information about patients allergies. This article defers the first step of our methodological cycle by explaining how collaboration is organized between Pikcio (blockchain technology provider) and allergists. As a result, we have first versions of some deliverables such as formal specifications, risk matrix document and a UML design (class diagram, use case diagram and sequence diagram) as the research project is iterative
