Two cases of fatal anaphylaxis caused by seafood allergy are reported. The first serves as a reminder of the importance of obtaining a full medical history and details of the circumstances of death, and of the need to be aware of forensic post-mortem artefacts. Observations on the immunological mechanisms of type 1 or immediate hypersensitivity seen in the second case, and a discussion of preventive measures, offer subjects for medicolegal deliberation.