Definition:
The reactions assessed are isolated febrile type (not associated with other specific reaction categories), allergic and hypotensive reactions occurring up to 24 hours following a transfusion of blood or components, for which no other obvious cause is evident.
SHOT has collected data on febrile, allergic and hypotensive reactions (FAHR) since 1996. Originally, this category was called acute transfusion reactions (ATR).
Since 2012 SHOT has excluded ‘mild reactions’, and now only collects data on moderate or severe reactions according to the International Society for Blood Transfusion/International Haemovigilance Network (ISBT/IHN) definitions.
SHOT Transfusion Safety Standards
The SHOT Transfusion Safety Standards were released in July 2025, and these replace recommendations in the Annual SHOT Reports. More details on these can be found at: https://www.shotuk.org/transfusion-safety/transfusion-safety-standards/
Recommendations from recent Annual SHOT Reports (prior to 2024)
Give appropriate targeted treatment and if needed, preventative cover for future transfusion
Haematology registrars should receive training in classification, appropriate investigation and management of transfusion reactions in the laboratory induction at the start of their programme
Action: Hospital transfusion teams, Haematology training programme directors
Please see the individual SHOT chapters at the end of the page for other previous recommendations which remain relevant.
FAHR Resources
SHOT Bite No.05a: Febrile, Allergic and Hypotensive Reactions (FAHR) – Getting the diagnosis right
SHOT Bite No.05b FAHR investigations
FAHR Annual Report Chapters
To access the chapter click either on the cover of the Annual SHOT Report or the link below the picture
