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Constipation in Children


Deborah M. Consolini

, MD, Sidney Kimmel Medical College of Thomas Jefferson University

Last full review/revision Jun 2020| Content last modified Jun 2020

Constipation refers to delay or difficulty in passing stool for a period of at least 1 month in infants and toddlers and a period of 2 months in older children (see also Constipation in adults). Stools are harder and sometimes larger than usual and may be painful to pass. Constipation is very common among children. It accounts for up to 5% of children’s visits to the doctor. Infants and children are particularly prone to developing constipation at three periods of time. The first period is when cereals and solid food are introduced into the infant's diet, the second period is during toilet training, and the third period is around the start of school.

The frequency and consistency of bowel movements (BMs) vary throughout childhood, and there is no single definition of what is normal. Newborns typically have 4 or more stools per day. During the first year, infants have 2 to 4 a day. Breastfed infants typically have more BMs than formula-fed infants and may have one after each breastfeeding. The stools of breastfed infants are loose, yellow, and seedy. After a month or two, some breastfed infants have BMs less frequently, but the stools remain mushy or loose. After 1 year of age, most children have one or sometimes two soft but formed stools a day. However, some infants and young children typically have BMs only once every 3 to 4 days.

Guidelines for identifying constipation in infants and children include

  • No BMs for 2 or 3 more days than usual
  • Hard or painful BMs
  • Large stools that may clog the toilet
  • Drops of blood on the outside of the stool

In infants, signs of effort such as straining and crying before successfully passing a soft stool usually do not indicate constipation. These symptoms are usually caused by failure to relax the pelvic floor muscles during passage of stool and typically resolve spontaneously.

Parents often worry about their child's BMs, but constipation usually has no serious consequences. Some children with constipation regularly complain of abdominal pain, particularly after meals. Occasionally, passing large, hard stools may cause a small tear in the anus (anal fissure). Anal fissures are painful and may result in streaks of bright red blood on the outside of the stool or on toilet paper. Rarely, chronic constipation can contribute to urinary problems such as urinary tract infections and bed-wetting.

Causes of Constipation in Children

Common causes

In 95% of children, constipation results from

  • Dietary issues
  • Behavioral issues

Constipation that results from dietary or behavioral issues is called functional constipation.

Dietary issues that cause constipation include a diet that is low in fluids and/or fiber (fiber is present in fruits, vegetables, and whole grains).

Behavioral issues that may be associated with constipation include stress (as may be felt when a sibling is born), resistance to toilet training, and a desire for control. Also, children may intentionally put off having BMs (called stool withholding) because they have a painful anal fissure or because they do not want to stop playing. Sexual abuse may result in stress or injury that causes children to withhold stool. If children do not move their bowels when the natural urge comes, the rectum eventually stretches to accommodate the stool. When the rectum has stretched, the urge to have a BM lessens, and more and more stool accumulates and hardens. A vicious circle of worsening constipation may result. If the accumulated stool hardens, it sometimes blocks the passage of other stool—a condition called fecal impaction. Looser stool from above the hardened stool may leak around the impaction into the child's underwear and lead to stool incontinence (encopresis). Parents may then think that the child has diarrhea when the actual problem is constipation.

Less common causes

In about 5% of children, constipation results from a physical disorder, drug, or toxin. Disorders may be apparent at birth or develop later. Constipation that results from a disorder, drug, or toxin is called organic constipation.

In newborns and infants, the most common disorder that causes organic constipation is

Other causes of organic constipation include

Children with serious abdominal disorders (such as appendicitis or a blockage in the intestine) often do not have BMs. However, these children typically have other, more prominent symptoms, such as abdominal pain, swelling, and/or vomiting. These symptoms typically lead parents to seek medical care before the number of BMs decreases.

Evaluation of Constipation in Children

Doctors first try to determine whether constipation results from dietary or behavioral issues (functional) or from a disorder, toxin, or drug (organic).

Warning signs

Certain symptoms are cause for concern and should raise suspicion for an organic cause of constipation:

  • No bowel movements (BMs) during the first 24 to 48 hours after birth
  • Weight loss or poor growth
  • Decreased appetite
  • Blood in the stools
  • Fever
  • Vomiting
  • Abdominal swelling
  • Abdominal pain (in children old enough to communicate this)
  • In infants, loss of muscle tone (the infant appears floppy or weak) and reduced ability to suck
  • In older children, an involuntary release of urine (urinary incontinence), back pain, leg weakness, or problems with walking

When to see a doctor

Children should be evaluated by a doctor right away if they have any warning signs. If no warning signs are present but the child is passing infrequent, hard, or painful BMs, then the doctor should be called. Depending on the child's other symptoms (if any), the doctor may advise trying simple home treatments or ask the parents to bring the child for an examination.

What the doctor does

Doctors first ask questions about the child's symptoms and medical history. Doctors then do a physical examination. What they find during the history and physical examination often suggests a cause of the constipation and the tests that may need to be done (see table Some Physical Causes and Features of Constipation in Infants and Children).

Doctors determine whether newborns have ever had a BM (the first BM is called meconium). Newborns who have not had a BM within 24 to 48 hours after birth should have a thorough examination to rule out the possibility of Hirschsprung disease, anorectal malformations, or other serious disorder.

For infants and older children, doctors ask whether constipation began after a specific event, such as introducing cereal or other solid foods, eating honey, beginning toilet training, or starting school. For all age groups, doctors ask about diet and about disorders, toxins, and drugs that can cause constipation.

For the physical examination, doctors first look at the child overall for signs of illness and measure height and weight to check for signs of delayed growth. Doctors then focus on the abdomen, the anus (including examination of the rectum using a gloved finger), and nerve function (which can affect how the digestive tract functions).


If the cause of constipation appears to be functional, no tests are needed unless children do not respond to treatment. If children do not respond or if doctors suspect that the cause is another disorder, an x-ray of the abdomen is taken, and tests for other disorders are done based on the results of the examination.

Some Physical Causes and Features of Constipation in Infants and Children


Common Features*


Birth defects of the anus

Abnormal position of the anus

Opening of the anus that appears closer than normal to the genitals

Measurements to determine the exact location of the anus’s opening

Anal stenosis (a narrowed anus)

Delayed passage of the first BM (called meconium) during the first 24–48 hours of life

Explosive and painful BMs

A swollen abdomen

Abnormal appearance or position of the anus

A doctor's examination

Blockage of the opening of the anus (anorectal malformations)

A swollen abdomen

No BMs

A blockage of the anus detected during a doctor's examination

A doctor's examination done soon after birth

Spinal cord problems

Meningomyelocele (the most severe form of spina bifida)

A raw, red area on the back where the spinal cord protrudes, seen at birth

A decrease in reflexes of the legs or in muscle tone

Absence of the normal reflex of the anus (a tightening when lightly touched, called anal wink)

Plain x-rays of the lower spine

MRI of the spine

Occult spina bifida (incomplete formation of the bones of the spine)

Possibly a tuft of hair or dimpling on the skin over the defect, seen at birth

MRI of the spine

A tethered spinal cord (during fetal development, the spinal cord is stuck at the lower end of the spinal column and cannot move up to its normal position)

Problems with walking, pain or weakness in the legs, and back pain

Urinary incontinence

MRI of the spine

A tumor near the tailbone (sacral teratoma) or other spinal cord tumor

Back pain, problems with walking, and pain or weakness in the legs

Urinary incontinence

MRI of the spine

Infection of the spine or spinal cord

Back pain, problems with walking, and pain or weakness in the legs


Urinary incontinence

MRI of the spine

Hormonal, metabolic, or electrolyte disorders

Diabetes insipidus (due to problems with antidiuretic hormone, which helps regulate the amount of water in the body)

Excessive thirst and excessive crying that is quieted by giving children water

Excessive urination of dilute urine

Weight loss and vomiting

Urine and blood tests to measure how dilute urine and blood are (osmolality)

Blood tests to measure antidiuretic hormone levels

Hypercalcemia (an abnormally high calcium level in the blood)

Nausea and vomiting, loss of appetite, weight loss, muscle weakness, and abdominal pain

Excessive thirst and excessive urination

Blood tests to measure the calcium level

Hypokalemia (an abnormally low potassium level in the blood)

Muscular weakness

Excessive urination and dehydration

Not growing as expected (failure to thrive)

Possibly use of diuretics or certain antibiotics

Blood tests to measure levels of electrolytes

Hypothyroidism (an underactive thyroid gland)

Poor feeding

A slow heart rate

In newborns, large soft spots (fontanelles) between the skull bones and slack muscle tone

Dry skin, intolerance of cold, fatigue, and jaundice

Blood tests to measure thyroid hormone levels

Intestinal disorders

Cystic fibrosis

Delayed passage of the first BM

Poor weight gain or failure to thrive

Frequent bouts of pneumonia

A sweat test

Possibly genetic testing to confirm the diagnosis

Hirschsprung disease

Delayed passage of the first BM

A swollen abdomen

Green or yellow vomit, indicating that it contains bile

A narrowed anus detected during a doctor's examination

X-rays of the lower digestive tract after barium is inserted in the rectum (barium enema)

Measurement of pressure inside the anus and rectum (manometry)

Biopsy of the rectum

Allergy to cow's milk protein


Poor feeding

Weight loss, poor growth, or both

Blood in stools

Stool tests

Symptoms that lessen when the formula is changed

Possibly endoscopy, colonoscopy, or both

Celiac disease

Abdominal pain


Weight loss


Blood tests


Irritable bowel syndrome

Long-standing (chronic) abdominal pain

Diarrhea and constipation that come and go

A feeling of incomplete emptying after a BM

Evaluation of BM patterns and the timing and characteristics of pain

Exclusion of other disorders by history, physical examination, and possibly blood tests, stool tests, imaging, or colonoscopy

Pseudo-obstruction (which causes symptoms of a blockage but no blockage is detected)

Nausea and vomiting

Abdominal pain and a swollen abdomen

X-ray of the abdomen

Tests to assess how well the bowel functions (bowel motility studies)

A tumor in the abdomen

Weight loss, night sweats, and fever

Abdominal swelling or pain

An abdominal mass detected during a doctor's examination


Drug side effects

Use of drugs with anticholinergic effects(such as antihistamines), antidepressants, chemotherapy drugs, or opioids

Use of drugs that can cause constipation

A doctor's examination


Infant botulism

A sudden reduction in the ability to suck

Loss of muscle tone

Sometimes consumption of honey before age 12 months

A test for botulinum toxin in stool

Lead poisoning

Usually no symptoms

Possibly abdominal pain, fatigue, and irritability

Regression in development

Blood tests to measure the lead level

* Features include symptoms and results of the doctor's examination. Features mentioned are typical but not always present.

BM = bowel movement; MRI = magnetic resonance imaging.

Treatment of Constipation in Children

Treatment of constipation depends on the cause.

For organic constipation, the causative disorder, drug, or toxin is treated, corrected, or removed.

For functional constipation, measures include

  • Changing the diet
  • Modifying behavior
  • Sometimes using stool softeners or laxatives

Changing the diet

Dietary changes for infants include giving them 1 to 4 ounces (30 to 120 milliliters [mL]) of prune, pear, or apple juice each day. For infants younger than 2 months, 1 teaspoon (5 mL) of light corn syrup can be added to their formula in the morning and evening.

Older infants and children should increase their consumption of fruits, vegetables, and high-fiber cereals and decrease consumption of constipating foods, such as milk and cheese.

Modifying behavior

Behavioral modification can help older children. Measures include

  • Encouraging children who are toilet trained to sit on the toilet for 5 to 10 minutes after meals and encouraging them when they make progress (for example, noting progress on a wall chart)
  • Giving children who are being toilet trained a break from toilet training until constipation resolves

Sitting on the toilet after a meal can help because eating a meal triggers a reflex to have a BM. Frequently, children ignore the signals from this reflex and put off having a BM. This technique uses the reflex to help retrain the digestive tract, establish a toilet routine, and encourage more regular BMs.

Stool softeners and laxatives

If constipation does not respond to behavioral modification and changes in diet, doctors may recommend certain drugs that help soften stool (stool softeners) and/or increase the spontaneous movement of the digestive tract (laxatives). Such drugs include polyethylene glycol, lactulose, mineral oil, milk of magnesia (magnesium hydroxide), senna, and bisacodyl. Many of these drugs are now available over the counter. However, doses should be based on the age and body weight of the child as well as the severity of constipation. Thus, parents should consult a doctor regarding the appropriate dose and number of doses per day before using these treatments. The goal of treatment is the passage of one soft stool per day.

If children have a fecal impaction, options include gentle enemas and agents (such as mineral oil or polyethylene glycol) taken by mouth with large amounts of fluid. If these treatments are ineffective, children may need to be hospitalized to have the impaction removed.

Infants do not usually require any of these treatments. Typically, a glycerin suppository is adequate.

To maintain regular BMs, some children may require fiber supplements (such as psyllium), which may be obtained without a prescription. For these supplements to be effective, children must drink 32 to 64 ounces of water a day.

Key Points about Constipation in Children

  • Usually, constipation is caused by behavioral or dietary issues (called functional constipation).
  • Children should be evaluated by a doctor if the interval between BMs has been 2 or 3 days more than usual, if their stools are hard or large, if stools cause pain or bleeding, or if children have other symptoms.
  • If a newborn does not have a BM within 24 to 48 hours after birth, a thorough evaluation should be done to rule out the presence of Hirschsprung disease or another serious disorder.
  • Addition of fiber to the diet or behavioral modification can help when dietary or behavioral issues are the cause.

Drugs Mentioned In This Article

Generic Name Select Brand Names
lactulose CHOLAC
bisacodyl DULCOLAX
codeine No US brand name

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