Objective:To investigate the efficacy and safety of polyethylene glycol 4000 (Forlax(R)) on adult patients with functional constipation due to posttraumatic confinement to bed.Methods: A total of 201 posttraumatic bedridden patients were studied in this prospective,open-labeled, singlegroup study. Polyethylene glycol 4000 was administered orally for 14 days and the dosage was adjusted according to the Bristol stool types. Demographic characteristics, disease status, treatment period and factors affecting clinical outcome, especially the concomitant medications, were recorded.Results:After administration of polyethylene glycol 4000, 194 cases (96.52%) showed remission of constipation,including 153 (76.12%)persistent remission. The average defecation frequency increased significantly after treatment and the percentage of patients with stools of normal types (Bristol types 3-5) increased as well. Genders, ages and concomitant medications showed no significant influence on the persistent remission rate. After consecutive treatment for two weeks, patients with slight movement showed a significantly higher remission rate than those without movement (95% vs 80%). At the end of treatment, most accompanying symptoms were relieved obviously. Patients with a medical history of constipation or ever taking laxatives showed a lower remission rate. Sixty cases (29.85%) developed diarrhea during the observational period, among whom 6 (10%) withdrew from the clinical observation voluntarily at the first onset of diarrhea. Two cases suffered from abdominal pain.Conclusions:Polyethylene glycol 4000 (Forlax(R)) has efficacy on functional constipation in posttraumatic bedridden patients. Furthermore, patients with milder symptoms,more movement in bed, and longer duration of treatment but without accompanying symptoms can achieve a higher remission rate.