Comparing Two Different Concentrations of Diphenhydramine Versus Lidocaine for Median Nerve Block in Emergency Department: A Double-Blind Randomized Clinical Trial

Aim:This study aimed to compare two different concentrations of Diphenhydramine vs. Lidocaine for median nerve block in terms of providing required anesthesia for repairing soft tissue injuries.Materials and Methods:This double-blind, randomized clinical trial was conducted in Tehran, Iran, in 2019. Participants were randomly assigned to three groups. Group A received 3 cc of 0.5% diphenhydramine (n=68), group B received 3 cc of 1% lidocaine (n=68), and group C received 3 cc of 1% diphenhydramine (n=68). The onset of action, duration of anesthesia, pain during injection, and patients’ satisfaction level were evaluated between the groups.Results:Two hundred two patients with the mean age of 35.09±13.5 years took part in this study (52.5% of the males). Age (p=0.879), onset of action (p=0.251) and duration of anesthesia (p=0.081) had no significant difference among the three groups. The pain during injection between groups A and B (p=0.001) and between groups B and C (p<0.0001) had significant differences. Patients in group B had the significant highest level of satisfaction (p