Persistent Post-Burn Pruritus Following Antihistamine Initiation: A Retrospective Longitudinal Study at a Single...

Background/Objectives: An operationally defined unchanged itch-score sequence may indicate persistent symptoms rather than symptom resolution. We described pruritus following antihistamine initiation in children with burns and examined how its apparent stabilization depended on the analytical definition. Methods: This retrospective single-center study included 247 children. Daily scores were reconstructed from clinical charts using IMS-derived and TPIS-derived coding frameworks. Analyses added during revision examined alternative stability rules, candidate breakpoints, separate tool-specific trajectories and missingness. Results: Mean normalized itch decreased from 0.836 on Day 0 to 0.628 on Day 2 and 0.605 on Day 3 and then ranged from 0.591 to 0.608 through Day 14. All 3210 observed scores remained above zero, including all 197 available Day-14 assessments; 50 Day-14 scores were missing. A post hoc rule requiring three unchanged consecutive daily scores after at least one category of improvement was met by 177/247 children (71.7%), with a conditional median confirmation day of 4 (IQR 3-5). Alternative rules gave medians of 3 and 5. Candidate model comparisons favored Day 2; age/tool trajectories differed (p < 0.001). Adjusted models included 2654 observations from 205 children. Conclusions: The recorded trajectory showed early reduction followed by little change in mean itch, with persistent symptoms in observed assessments. The timing of operational score-stability events depended on the definition applied. Neither a drug effect nor a validated clinical reassessment threshold can be inferred.