A Randomized Controlled Trial of Glycerin Suppositories During Phototherapy in Premature Neonates

Objective To determine if glycerin suppositories were effective in reducing total duration of phototherapy in premature neonates. We hypothesized that glycerin suppositories would have no effect on phototherapy duration or total serum bilirubin levels. Design Prospective randomized controlled double-blinded trial. Setting Level IV NICU. Participants Neonates born between 30 weeks, 0 days and 34 weeks, 6 days gestational age who developed physiologic hyperbilirubinemia needing phototherapy. Methods Neonates were randomized to the no-suppository group or to the suppository group. Neonates were randomized to receive glycerin suppositories every 8 hours while under phototherapy or to a sham group. The primary outcome was total hours of phototherapy. Secondary outcomes included peak total serum bilirubin levels, time from start to discontinuation of phototherapy, rate of decline in bilirubin levels, repeat episodes of phototherapy, and number of stools while the neonates received phototherapy. Results A total of 39 neonates were assigned to the no-suppository group and 40 to the suppository group. Withholding suppositories was not inferior to providing suppositories. The total hours of phototherapy were not longer (i.e., noninferior) among neonates not provided suppositories (61 ± 53 hours) than among those given suppositories (72 ± 49 hours). There were no differences in peak bilirubin levels, rate of bilirubin decline, or repeat episodes of phototherapy. Conclusion Routine use of glycerin suppositories among preterm neonates who receive phototherapy does not affect bilirubin levels or phototherapy duration.