Tehran University of Medical Sciences Iranian Journal of Allergy, Asthma and Immunology 1735-1502 17 1 2018 02 26 94 96 EN Stefanie Aurich Department of Dermatology, Venereology and Allergology, University Hospital, Leipzig, Germany AND LICA-Leipziger Interdisziplinäres Centrum für Allergologie, University Hospital, Leipzig, Germany Jan-Christoph Simon Department of Dermatology, Venereology and Allergology, University Hospital, Leipzig, Germany AND LICA-Leipziger Interdisziplinäres Centrum für Allergologie, University Hospital, Leipzig, Germany Regina Treudler Department of Dermatology, Venereology and Allergology, University Hospital, Leipzig, Germany AND LICA-Leipziger Interdisziplinäres Centrum für Allergologie, University Hospital, Leipzig, Germany 2016 06 24 2016 07 25 We report a 78 year-old non-atopic female with polyneuropathy who started to receive monthly intramuscular injections of thiamine hydrochloride. She had an anaphylaxis after the fourth injection. Skin prick test (SPT) with pure commercially available aqueous preparations was positive for thiamine hydrochloride. A titrated, single blinded, placebo-controlled oral provocation test with thiamine hydrochloride was well tolerated. The patient was then diagnosed as compartment allergy with hypersensitivity to parenteral but not to oral thiamine. Because in our patient, oral intake of thiamine has never been reported to lead to any adverse reaction. Oral tolerability might be due to the uptake mechanism of thiamine in the gastrointestinal system. https://ijaai.tums.ac.ir/index.php/ijaai/article/view/981 https://ijaai.tums.ac.ir/index.php/ijaai/article/download/981/808