A comparative study: the efficacy of liquid paraffin and lactulose in management of chronic functional constipation

Pediatr Int. 2005 Feb;47(1):15-9. doi: 10.1111/j.1442-200x.2004.02001.x.


Objectives: To determine and compare efficacy, safety and optimal dose of two laxatives, liquid paraffin and lactulose, in 40 children with chronic functional constipation.

Methods: A total of 20 children were treated with liquid paraffin and 20 with lactulose for 8 weeks and at an initial dose of 1 mL/kg per day for both drugs. The dose was adjusted every 3 days as required and a diary was kept to monitor dose, side-effects, stool frequency and consistency, and other symptoms.

Results: During first 4 weeks, improvement in stool consistency and frequency was significantly higher in liquid the paraffin group (P < 0.01 and P < 0.05, respectively). Improvement in the number of stools per week was also significantly higher in the liquid paraffin group during the last 4 weeks of therapy (P < 0.05). Compliance rates averaged 95% in the liquid paraffin group and 90% in the lactulose group during the first 4 weeks of therapy and 90% in the liquid paraffin group and 60% in the lactulose group during the last 4 weeks of therapy (chi(2) = 4.8, SD = 1, P = 0.02). During the first 4 weeks of therapy and during the last 4 weeks of therapy, mostly side-effects and poor symptom control, respectively, influenced the compliance in the liquid paraffin group.

Conclusions: Liquid paraffin is more effective in the treatment of children with constipation. Patients treated with liquid paraffin responded more rapidly than patients responding to lactulose and showed fewer side-effect. It is considered that late response and side-effects in conjunction with poor symptom control influence the patient compliance and the successful treatment of childhood constipation.

Publication types

  • Clinical Trial
  • Randomized Controlled Trial

MeSH terms

  • Cathartics / therapeutic use*
  • Child
  • Child, Preschool
  • Constipation / prevention & control*
  • Female
  • Gastrointestinal Agents / therapeutic use*
  • Humans
  • Lactulose / therapeutic use*
  • Male
  • Mineral Oil / therapeutic use*
  • Patient Compliance
  • Prospective Studies
  • Time Factors


  • Cathartics
  • Gastrointestinal Agents
  • Lactulose
  • Mineral Oil