Review of Fixed Food Eruptions

Fixed food eruption (FFE) is a rare cutaneous reaction characterized by the recurrence of skin lesions at the same sites following ingestion of specific food triggers. This review aims to address gaps in the literature by synthesizing findings from published cases and studies on FFE. A systematic search of the databases MEDLINE, Embase, Cochrane Central Register of Controlled Trials, and Web of Science was conducted on April 11, 2025. After screening for duplicates and excluding irrelevant studies, 32 studies were included in the review. Results showed that there was a greater prevalence of FFE documented in women (63.9%, n = 39) and patients over 18 years old (73.7%, n = 45). The most frequent offending agent identified was tonic water in 24.1% of cases (n = 15). The next most common triggers were cashew nuts and peanuts in 8.1% of cases each (n = 5). The onset of FFE was noted to be less than 4 hours after exposure in 67.2% of cases (n = 41). To diagnose FFE, the majority of studies, 78.6% (n = 48), utilized an oral challenge with the suspected agent to confirm association with the fixed eruption. Patch tests, 49.1% (n = 30), and biopsies, 21.3% (n = 13), were also frequently utilized. Negative patch tests on either previously affected or unaffected skin were also noted in 49.1% of cases (n = 30). Of note, only 29.5% (n = 18) of cases reported any form of treatment, and 72.2% (n = 13) of these reported trigger avoidance as the only form of management. To our knowledge, this is the first comprehensive review of FFE, synthesizing data on demographics, triggers, and diagnostic techniques.