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Constipation in Children


Deborah M. Consolini

, MD, Thomas Jefferson University Hospital

Reviewed/Revised Nov 2022
Topic Resources

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 Constipation in Adults Constipation is difficult or infrequent bowel movements, hard stool, or a feeling that the rectum is not totally empty after a bowel movement (incomplete evacuation). (See also Constipation... read more 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 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.

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 Sexual abuse Child maltreatment includes all types of abuse and neglect of a child under the age of 18 by a parent, caregiver, or another person in a custodial role (for example, clergy, coach, or teacher)... read more 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 Stool Incontinence in Children Stool incontinence is the inappropriate passing of bowel movements that is not caused by illness or physical abnormality. Stool incontinence can be voluntary or involuntary. It occurs in about... read more (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 and needs to be evaluated by a doctor.

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

Other causes of organic constipation include

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:

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 Treatment 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)... read more 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 Some Physical Causes and Features of Constipation in Infants and Children 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 under 12 months of age, 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 X-Rays X-rays are a type of medical imaging that use very low-dose radiation waves to take pictures of bones and soft tissues. X-rays may be used alone (conventional x-ray imaging) or combined with... read more of the abdomen is taken, and tests for other disorders are done based on the results of the examination.


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, doctors may recommend that children use 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 (about 1 to 2 liters) of water a day.

Key Points

  • 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
No brand name available
ARYMO ER, Astramorph PF, Avinza, DepoDur, Duramorph PF, Infumorph, Kadian, MITIGO, MORPHABOND, MS Contin, MSIR, Opium Tincture, Oramorph SR, RMS, Roxanol, Roxanol-T
GaviLax, GIALAX , GlycoLax, Healthylax, MiraLax, Visine Dry Eye Relief, Vita Health
Acilac, Cephulac, Cholac, Chronulac, Constilac, Constulose, Enulose, Generlac, Kristalose
Fleet, Kondremul, Liqui-Doss, Muri-Lube
Dulcolax, Dulcolax Chewy Fruit Bites, Dulcolax Kids, Ex-Lax, Fleet Pedia-Lax, Freelax, Phillips Laxative, Phillips Milk of Magnesia
Black Draught , Ex-Lax, Fletchers Laxative, Geri-kot, Lax-Pills, Little Remedies for Tummys, OneLAX, Perdiem, Plus PHARMA, Senexon, Senna, SennaGen , Senna-Lax , Senna-Tabs, Senna-Time, Sennatural, Senokot, Senokot Extra Strength , Senokot Xtra, SenoSol, SenoSol-X, Uni-Cenna
Alophen, Bisac-Evac , Biscolax, Corrective Laxative for Women, Correctol, Dacodyl, Doxidan, Dulcolax, Ex-Lax Ultra, Feen-A-Mint , Fematrol , Femilax, Fleet, Laxative, OneLAX, Reliable Gentle Laxative, Veracolate
Colace Glycerin, Fleet, Fleet Pedia-Lax, HydroGel, Introl , Lubrin, Orajel Dry Mouth, Osmoglyn, Sani-Supp
Fiber Therapy, GenFiber , Geri-Mucil, Hydrocil , Konsyl, Metamucil, Metamucil MultiHealth, Mucilin , Natural Fiber Laxative, Natural Fiber Therapy, Reguloid
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