Patients were selected from 224 children attending imam Reza pediatric gastroenterology clinic. The children with diagnosis of functional constipation based on Rome III criteria , for at least 3 months before diagnosis and age between 4-18 years old were considered for inclusion study. Children having the Rome III criteria for Inflammatory bowel disease or organic causes of defecation disorders such as Hirschsprung's disease, spina bifida occulta, hypothyroidism, cystic fibrosis, neurologic abnormalities, intestinal pseudo-obstruction, and diabetes mellitus were excluded from the study.
3. Study procedure
A three months, prospective, randomized clinical trial was performed. Through a block randomization, patients were divided into two parallel therapeutic groups (60 patients in each group). The sample size was determined based on a previous study . Totally, 120 children were allocated into cupping therapy and PEG groups. The methodologist and the statistician who assessed and analyzed the data were blind to the protocol.
At enrollment, a complete history was taken and physical examination done by a pediatrist involved in the study. Baseline frequency of defecation, presence of fecal soiling (encopresis), hard stool consistency, retention posturing and abdominal pain was recorded.
In both groups, an expert person instructed routine nutritional and behavioral recommendations for children's constipation. Patients with fecal impaction in both groups were also disimpacted with bisacodil suppositories at the first visit before enrolment. The parents were instructed to call the researcher if they observed any adverse effect or had any question.
In a cupping group, a registered operator of cupping therapy explained the method, duration, sites and frequency of cupping therapy to participants' parents and cupped the patients under their parents view. In a second session, the parents cupped their children under supervision of the instructor to adopt and correct the procedure. The remained 12 session of cupping were done by the parents at home every other day (totally 28 days of cupping therapy). Patients were excluded from the study if they had no bowel movement for seven days or developed fecal impaction, at any stage.
Medication was oral administration of PEG (40% solution without electrolyte), 0.4 g/kg once daily for 4 weeks. Parents were requested to refer to call the pediatrist in confronting with any complication. Weekly reports were taken from by the interviewer. Patients were followed after 2, 4 , 8 and 12 weeks of intervention.
Various sterile disposable cups (manufactured in ABC ®, a chinese company) from 1.5 cm to 5 cm in diameter (10 – 100 cc) were used (regard to patient age). ّour to six cups (regard to patient skin surface) were applied on the abdominal skin (not on umbelicus) in each session. Duration of cupping therapy was 8 minutes. The negative pressure was applied until skin became congested. After that, the cup was remained on the skin until 7 minutes. Then the regulating button on back of the cup was pulled to release the cup from the skin. The potential changes of skin color until a few days after cupping therapy were explained to the parents.