ObjectiveThis study aimed to investigate the clinical effects of recombinant human interleukin-11 (rhIL-11) gargle on preventing and treating oral mucositis (OM) after chemotherapy for acute leukemia.MethodsThis single-site, prospective, observer-blinded, nonrandomized controlled trial was conducted on 74 patients with acute leukemia, who were divided into the experimental and control groups. The patients in the experimental group were treated with IL-11 gargle, and those in the control group were treated with sodium bicarbonate gargle. We examined the time and severity of oral mucositis, severity and duration of associated pain, healing time of mucositis, effects of OM on eating, and levels of T-cell subset indicators before and after treatment to evaluate the effects of IL-11 treatment.ResultsThe proportion of patients with severe OM was significantly lower in the experimental group than in the control group. Mucositis occurred later in the experimental group compared with the control group. The degree and duration of pain, ulcer healing time, and effects on eating were lower in the experimental group compared with the control group. Following treatment, the levels of all T-cell subset indicators improved in each of the two groups. However, the rate of improvement was significantly higher in the experimental group than in the control group. These differences were statistically significant (P< 0.05).ConclusionsIL-11 gargle reduced the severity of OM after chemotherapy for acute leukemia. Treatment with IL-11 relieved pain, promoted healing, and improved the curative effect of the condition, making it worthy of clinical promotion.