Abstract
BACKGROUND: Previous studies have demonstrated the efficacy of melatonin in alleviating symptoms of irritable bowel syndrome (IBS) and improving quality of life (QoL). OBJECTIVES: Due to its superior bioavailability, this trial was designed to compare the effects of sublingual melatonin (SL melatonin) with a placebo in alleviating IBS symptoms, enhancing QoL, and addressing sleep disorders. METHODS: The IBS patients were randomly assigned to receive either 3 mg of SL melatonin or a matching placebo for eight weeks. Participants completed the IBS symptom severity score (IBS-SSS), IBS-quality of life 34 items (IBS-QoL 34), and Pittsburgh Sleep Quality Index (PSQI) questionnaires immediately before and after the study period. RESULTS: A total of 76 patients completed the trial over six months. The results indicated that the severity of IBS symptoms and QoL scores were significantly better in the SL melatonin group compared to the placebo group (P = 0.032 and P = 0.045, respectively). No participants withdrew from the trial due to serious side effects in either the SL melatonin or placebo groups. CONCLUSIONS: Sublingual melatonin may be administered to IBS patients as a complementary treatment to alleviate symptoms and improve QoL.