The Efficacy and Palatability of Developed Polyethylene Glycol-based Formula for Children With Functional Constipation

Total 52 children age 6 months to 18 years old diagnosed with functional constipation will be enrolled in this study. They will be randomised in Group A or Group B.

Children in group A will receive PEG-Chula at a dose of 0.5 - 1 g/kg/day for a duration of 56 days.

Children in group B will receive the standard PEG formula (Forlax) at a dose of 0.5 - 1 g/kg/day for a duration of 56 days.

PEG-Chula and standard PEG will be prepared in sachets with similar packaging and appearance labelled A, B, C, D.

Children in both groups will also receive counseling on toilet training, water intake, and fiber intake in the same manner.

Parents will be advised to record symptoms, dietary intake, and dose of medication in a logbook.

Children will visit the researchers on days 7, 14, 28, and 56 to collect data on symptoms, stool diameter, bowel size measured by ultrasound, side effects, and medication compliance. Children with poor compliance will be excluded from the study.

• Local PEG4000 (Drug), also known as PEG-Chula: PEG-Chula is developed from PEG 4000 used at King Chulalongkorn Memorial Hospital with added sweetener and flavours. Children will be given PEG-Chula at a dose of 0.5 - 1 g/kg/day.
• Commercial PEG4000 (Drug), also known as Forlax: For commercial PEG, We use Forlax as the control group. Children will be given Forlax at a dose of 0.5 - 1 g/kg/day.

Primary outcomes

• The frequency of stool [At 7 days, 14 days, 28 days and 56 days]: The frequency of stool per day
• Stool consistency assessed by Bristol stool chart [At 7 days, 14 days, 28 days and 56 days]: The Bristol stool chart has 7 pictures of stool appearance. The number 1 mean hard stool and number 7 mean watery stool

Secondary outcomes

• Fecal incontinence [At 7 days, 14 days, 28 days and 56 days]: Number of fecal incontinence occurs per day
• Rectal diameter measured by transabdominal ultrasonography [At 7 days, 14 days, 28 days, 56 days and 2 years]: Rectal diameter in centimeters is measured by transabdominal ultrasonography.
• Anterior wall thickness measured by transabdominal ultrasonography [At 7 days, 14 days, 28 days, 56 days and 2 years]: Anterior wall thickness in centimeters is measured by transabdominal ultrasonography.
• Adverse events [At 7 days, 14 days, 28 days and 56 days]: Adverse events (i.e diarrhea, abdominal pain, bloating, nausea or vomiting)
• Palatability of medication assessed by facial Hedonic scale [At 7 days, 14 days, 28 days and 56 days]: The facial Hedonic scale contains 5 pictures of facial expression and number 1 mean dislike very much while number 5 means like very much
• Change of gut microbiota before and after treatment [At baseline and 56 days]: Stools is collected before treatment at baseline and at the end of treatment. Gut microbiota was analyzed by Nanopore technique.

Sex: All, ages: 6 Months to 18 Years, accepts healthy volunteers

Inclusion Criteria:

Children will be enrolled in this study when they meet 2 criteria:

* Age from 6 months to 18 years old
* Children are diagnosed with FC according to ROME IV criteria

Exclusion Criteria:

Children will be excluded from the study if they meet any of the following criteria:

* Having an organic cause of constipation such as anorectal malformations, Hirschsprung disease, myelomeningocele, hypothyroidism, etc.
* Suspected GI obstruction
* Receiving medication affecting bowel movement
* Having a history of allergy to PEG and stevia.

• Palittiya Sintusek, Ph.D., Study chair, Chulalongkorn University