PT - JOURNAL ARTICLE AU - Chauhan, Dipesh AU - Prabhu, Anil AU - Cripps, Sarah AU - Misbah, Siraj AU - Griffiths, Kate AU - Roseman, Alice AU - Walsh, Alissa AU - Satsangi, Jack TI - Generalised urticaria and angioedema complicating switch back from subcutaneous to intravenous vedolizumab therapy AID - 10.1136/flgastro-2023-102380 DP - 2023 Sep 01 TA - Frontline Gastroenterology PG - 432--434 VI - 14 IP - 5 4099 - http://fg.bmj.com/content/14/5/432.short 4100 - http://fg.bmj.com/content/14/5/432.full SO - Frontline Gastroenterol2023 Sep 01; 14 AB - We report a unique case of a 34-year-old man with ulcerative colitis, previously in complete remission with intravenous vedolizumab monotherapy, who developed an urticarial injection-site reaction on switching to a subcutaneous preparation and thereafter experienced a new hypersensitivity reaction on switch back to intravenous vedolizumab, necessitating complete discontinuation from this drug. This case highlights the need for vigilance on switching back to intravenous preparations of vedolizumab, in response to injection-site reactions with a subcutaneous preparation, even if the intravenous preparation had been previously well tolerated by the patient.