Constipation as a diagnosis can be dangerous, mainly because it is a powerful anchor in our medical decision-making.
Chances are, you’d be right to chalk up the pain to functional constipation — 90% of pediatric constipation is functional, multifactorial, and mostly benign — as long as it is addressed.
We’re not here for “chances are“; we’re here for “why isn’t it?“
Ask yourself, could it be:
Anatomic malformations: anal stenosis, anterior displaced anus, sacral hematoma
Metabolic: hypothyroidism, hypercalcemia, hypokalemia, cystic fibrosis, diabetes mellitus, gluten enteropathy
Neuropathic: spinal cord abnormalities, trauma, tethered cord
Neuromuscular: Hirschprung disease, intestinal neuronal dysplasia, myopathies, Down syndrome, prune belly syndrome
Connective tissue disorders: scleroderma, SLE, Ehlers-Danlos syndrome
Drugs: opioids, antacids, antihypertensives, anticholinergics, antidepressants, sympathomimetics
Ingestions: heavy metals, vitamin D overload, botulism, cow’s milk protein intolerance
Red Flags
Failure to thrive
Abdominal distention
Lack of lumbosacral curve
Midline pigmentation abnormalities of the lower spine
Tight, empty rectum in presence of a palpable fecal mass
Gush of fluid or air from rectum on withdrawal of finger
Absent anal wink
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You gotta push the boat out of the mud before you pray for rain.
— Coach
Medications for disimpaction
(do this first!)
Polyethylene Glycol (PEG) 3350 (Miralax): 1 to 1.5 g/kg PO daily for 3 to 6 consecutive days. Maximum daily dose: 100 g/day PO. Follow-up with maintenance dose (below) for at least 2 months (usually 6 months)
Lactulose: 1.33 g/kg/dose (2 mL/kg) PO twice daily for 7 days
Mineral Oil (school-aged children): 3 mL/kg PO twice daily for 7 days
Medications for Maintenance
(do this after disimpaction!)
Polyethylene Glycol (PEG) 3350 (Miralax): 0.2 to 0.8 g/kg/day PO. Maximum daily dose: 17 g/day. Maintenance dosing for Miralax may need to be tailored; up to 1 g/day maintenance.
Lactulose: 1 to 2 g/kg/day (1.5 to 3 mL/kg/day)PO divided once or twice daily. Maximum daily dose: 60 mL/day in adults.
Mineral Oil: 1 to 3 mL/kg/day PO divided in 1 to 2 doses; maximum daily dose: 90 mL/day
Docusate (Colace): 5 mg/kg/day PO divided QD, BID, or TID (typical adult dose 100 mg BID)
Senna, Bisocodyl — complicated regimens; use your local reference
Enemas
- Are you sure? Have you tried oral disimpaction over days?
- No phosphate enemas for children less than 2.
- Saline enemas are generally safe for all ages
- Be careful with the specific dose — please use your local reference
Selected References
Freedman SB et al. Pediatric Constipation in the Emergency Department: Evaluation, Treatment, and Outcomes. JPGN 2014;59: 327–333.
North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition. Clinical Practice Guideline: Evaluation and Treatment of Constipation in Infants and Children. JPGN 2006; 43:e1-e13.
Tabbers MM et al. Evaluation and Treatment of Functional Constipation in Infants and Children: Evidence-Based Recommendations From ESPGHAN and NASPGHAN. JPGN 2014;58: 258–274.
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