Study to Examine the Efficacy and Safety of Movicol in the Treatment of Chronic Constipation in Children

Inclusion Criteria: Male and female patients of any ethnic origin will be eligible to participate in the study if all of the following criteria are fulfilled. * informed consent having been obtained from the patient's parent or guardian and assent from the child if they are capable of understanding the study * aged 24 months - 11 years * experiencing constipation as defined as: * ≤2 complete bowel movements per week, and at least one of the following: * pain on defaecation on ≥1 in 4 days * 1/4 or more of bowel movements with straining * 1/4 or more of bowel movements with hard or lumpy stools * patients in whom these symptoms have been present for ≥3 months * available to complete the study and able to comply with requirements and restrictions listed in the patient's/parent's information documents. Exclusion Criteria: Patients will not be eligible to participate in the study if any of the following conditions apply: * faecal impaction or history of faecal impaction * history of intestinal perforation or constipation * paralytic ileus * toxic megacolon * Hirschsprungs disease * severe inflammatory conditions of the intestinal tract * severe gastro-oesophageal reflux - that which is complicated by anaemia, haematemesis, respiratory aspiration, failure to thrive or other recognised complications of gastro-oesophageal reflux * patients currently receiving over 0.5mg/kg/day of senna or over 1/2 sachet of sodium picosulphate per day for children \<6 years and over 1 sachet sodium picosulphate per day for children \> 6 years (i.e. high doses of stimulant laxatives) * any other significant medical condition that in the investigator's opinion would effect their suitability for entry into the study * patients who have previously received Movicol or previously participated in the study * known hypersensitivity to polyethylene (PEG) 3350 or any of the constituents of Movicol * patients with diabetes as the placebo to be used in this study is sucrose * patients who have received any investigational drug in the last 3 months * patients and/or parents who the investigator thinks could not comply with the requirements of the protocol for any reason (particularly in relation to reliable completion of diary cards)