Topical lidocaine to improve oral intake in children with painful infectious mouth ulcers: a blinded, randomized, placebo-controlled trial.

STUDY OBJECTIVE: We establish the efficacy of 2% viscous lidocaine in increasing oral intake in children with painful infectious mouth conditions compared with placebo.

METHODS: This was a randomized placebo-controlled trial of viscous lidocaine versus placebo at a single pediatric emergency department. Study staff, clinicians, nurses, caregivers, and participants were blinded to the group assignment. Children with acute infectious ulcerative mouth conditions (gingivostomatitis, ulcerative pharyngitis, or hand, foot, and mouth disease) and poor oral fluid intake were randomized to receive 0.15 mL/kg of either 2% viscous lidocaine or placebo with identical appearance and flavor. The primary outcome was the amount of fluid ingested in the 60 minutes after administration of the intervention, with a difference in intake of 4 mL/kg considered clinically important. Secondary outcomes were specific milliliter per kilogram fluid targets and incidence of adverse events.

RESULTS: One hundred participants were recruited (50 per treatment group), all of whom completed the 60-minute fluid trial period. Oral intake 1 hour after drug administration was similar in both groups: lidocaine median 8.49 mL/kg (interquartile range 4.07, 13.84 mL/kg) versus placebo 9.31 mL/kg (interquartile range 3.06, 15.18 mL/kg); difference in medians 0.82 mL/kg (95% confidence interval -2.52 to 3.26); Mann-Whitney P=.90. Likewise, short-term secondary outcomes were similar between the groups and there were no adverse events in either group.

CONCLUSION: Viscous lidocaine is not superior to a flavored gel placebo in improving oral intake in children with painful infectious mouth ulcers.