EVIDENCE-BASED ANSWER
The best treatment for minor, self-limited constipation (infant dyschezia) may be observation and parental education about its benign nature. (Grade of recommendation: D, expert opinion.) For cases requiring treatment, limited evidence suggests that 2 weeks of 2% or 4% lactulose normalizes stool passage and consistency. (Grade of recommendation: C, single cohort study.) No data are available about the benefits or harms of rectal thermometer stimulation, glycerin suppositories, sorbitol or sorbitol-containing juices, barley malt extract, or corn syrup. The significant risks of sodium phosphate enemas and mineral oil consumption make their use contraindicated. (Grade of recommendation: D, case reports and expert opinion.)
Evidence summary
Infants experience normal physiologic variation in stool frequency and consistency, moderated in part by diet.1 Childhood functional defecation disorders represent a continuum from infant dyschezia, to functional constipation, to functional fecal retention2,3 (Table 1). Most infants have dyschezia or functional constipation. Infant dyschezia, a self-limited condition related to immature muscle coordination, requires only parental reassurance.
We found no placebo-controlled trials of osmotic laxatives in infants. One uncontrolled trial of 220 functionally constipated, bottle-fed infants younger than 6 months showed normalization of stools in 90% of infants within 2 weeks of treatment with 2% or 4% lactulose.4 No other evidence has been published about the benefits or harms of sorbitol-containing juices, fiber, osmotic laxatives, formula switching, rectal stimulation with rectal thermometers, or glycerin suppositories.
We found no trials of mineral oil or sodium phosphate enemas in constipated infants. Mineral oil has been associated with lipoid aspiration pneumonia in infants less than 1 year of age.5,6 Sodium phosphate enemas in children under 2 years of age have been associated with electrolyte disturbances, dehydration, and cardiac arrest.7
TABLE 1
Rome II childhood functional defecation disorders2
| Disorder, by age | Characteristics |
|---|---|
| Infant dyschezia (< 6 months old) | 10+ minutes of straining and crying before successful passage of stools. |
| Functional constipation (infancy to preschool years) | 2+ weeks of mostly pebble-like, hard stools for stools; or firm stools 2 times/wk; and no evidence of structural, endocrine, or metabolic disease. |
| Functional fecal retention (infancy to age 16) | 12+ weeks of passage of large-diameter stools at intervals < 2 times/wk; and retentive posturing, avoiding defecation by purposefully contracting the pelvic floor, then gluteal muscles. |
Recommendations from others
The North American Society for Pediatric Gastroenterology and Nutrition recommends glycerin suppositories for rectal disimpaction for acutely constipated infants; sorbitol-containing juices, such as prune, pear, and apple, for decreasing constipation; barley malt extract, corn syrup, lactulose, or sorbitol (osmotic laxatives) as stool softeners; and avoidance of enemas, mineral oil, and stimulant laxatives due to potential adverse effects8 (Table 2).
TABLE 2
Recommended interventions for infant constipation8
| Laxative | Dosage | Side effects | Comment |
|---|---|---|---|
| Glycerin suppositories | Standard | None reported | For rectal disimpaction |
| Sorbitol-containing juices | Variable | None reported | Prune, apple, pear |
| Barley malt extract | 2–10 mL/240 mL milk or juice | Unpleasant odor | Suitable for bottle-feeding |
| Corn syrup | Variable (light or dark) | None reported | Not considered source of C. botulinum spores |
| Lactulose (70% solution) | 1–3 mL/kg per day, divided doses | Flatulence, abdominal cramps, hypernatremia | Well-tolerated long-term |
| Sorbitol | 1–3 mg/kg per day, divided doses | Same as lactulose | Less expensive than lactulose |
Clinical Commentaries by Brian T. Easton, MD, and Susan E. Graves, MD, at http://www.fpin.org.