BACKGROUND Despite federally legislated safety regulations, caustic ingestions remain a significant problem in the pediatric population. The current standard of care for caustic ingestion includes upper gastrointestinal endoscopy in most cases. Hair relaxers are a common caustic ingestion at our institution, yet few data have been published describing the clinical or endoscopic outcome. We explored the relative frequency of hair relaxer ingestion, the incidence of associated upper gastrointestinal injury, and the adverse clinical sequelae resulting from these ingestions. METHODS Consecutive caustic ingestions admitted to our institution between January 1990 and January 2001 were identified. The data were collected through retrospective physician chart review, were analyzed, and were pooled with the existing literature to evaluate for the presence of esophageal injury. RESULTS 96 charts were reviewed, 29 (30%) of which were hair relaxer ingestions that underwent esophagogastroduodenoscopy; these ingestions served as our study cohort. The median age of the cohort was 14.0 months and patients were evenly divided in gender. The most common symptoms at presentation were drooling and emesis. At endoscopy, lip and oropharyngeal mucosa were most commonly affected. While six patients (20.7%) had Grade I esophageal mucosal injury and five patients (17.2%) had Grade I gastric mucosal injury, none had greater than Grade I mucosal damage. No adverse clinical events were identified. When our data were combined with all previously published cohort data, the findings were similar and no adverse clinical outcomes were reported. CONCLUSIONS Hair relaxer is the most common childhood caustic ingestion presenting to our large metropolitan tertiary care center. Symptoms are common at presentation. However, despite the high pH of these products, no clinically significant esophageal or gastric mucosal injuries and no long-term sequelae were identified.