Constipation is one of the most common intestinal problems affecting children, with some studies estimating that 50% of kids will deal with constipation at some point in their childhood. Fortunately, most constipation in infants and children is not caused by any serious underlying medical condition. This is known as functional constipation.
Constipation can look different from child to child. Some may experience hard stools, large stools, small pebbles or pellets, or even a mix of loose stools and hard pellets. Some kids with constipation may even go to the bathroom multiple times a day. This can happen when there is an issue with how their colon (the large intestine) is moving and sensing a bowel movement. To help treat this, healthcare providers may recommend physical therapy with laxatives, making the job of the colon easier by making bowel movements bulkier, softer, or triggering movement through the intestine. One thing to keep in mind is that constipation takes a LONG time to get better (like a sprain), and the shortest time we usually use laxatives is 2 months.
When Are Laxatives Used?
Once a cycle of constipation is established, it can be very hard to repair with hydration, fiber and diet alone. Typically, a laxative is recommended. These work either as “mushers” (laxatives that make stool softer, and bulkier, to trigger easier and more frequent bowel movements) or “pushers” (laxatives that cause the intestine to squeeze, pushing a bowel movement out). Parents are often worried about the long-term use of laxatives, but fortunately, the safety record of all commonly used laxatives is scientifically proven, and no concerns with long-term use of medically approved treatments have been noted.
Mushers
These medications work by either softening bowel movements, lubricating the colon, or bulking stool. The most commonly used example is fiber. Fiber is a non-absorbable complex carbohydrate that works by holding onto water to maintain a softer and larger stool that is easier to pass. Many products contain processed husk from psyllium (e.g., Metamucil, Konsyl), but other forms exist.
Lubricating agents are based on mineral oil and are not as commonly used as they were in the past, mainly due to the fact that kids do not normally like it, and if aspirated (inhaled into the lung) can cause injury. Remember that mineral oil does not get absorbed from the intestine: it is not a form of nondigestible fat (and need not be included in the calorie count). It provides lubrication and disperses the stool, preventing it from becoming compacted and dry.
A much less effective stool softener is docusate sodium (e.g., Colace, Laxinate 100). While available over the counter and still recommended by some providers, studies have shown it is not effective in treating constipation.
Osmotic laxatives function similarly to fiber but are not digestible by bacteria that live in our intestine, so they do not produce more gas, and are easier to tolerate than fiber at large doses. The most commonly used examples are various non-absorbable magnesium salts (milk of magnesia, magnesium citrate), or sodium phosphate, and polyethylene glycol 3350 (PEG), which is another non-absorbable product. PEG is an extremely safe and well tolerated medication that does not particularly absorb into the body, and perhaps the most prescribed treatment for constipation due to being very effective, and very safe.
Studies of chronic usage of PEG have shown no concern, and past reports linking it with autism spectrum disorder have been found to be inaccurate, as it is not PEG that causes autism, but instead that constipation and autism commonly occur together, and constipation gets diagnosed prior to autism frequently.
Newer types of medications are now available to help treat constipation. Some work by increasing the amount of fluid in the intestines, which helps soften stool and make bowel movements easier to pass. These medications are called secretagogues and include tenapanor, linaclotide, and lubiprostone. This type of medication works differently than a PEG (polyethylene glycol), which helps by holding the fluid you drink in the intestine to soften stool.
Other medications work by increasing movement in the colon to help move stool through the digestive tract. One example is prucalopride.
Treatment options in children are limited. Linaclotide is currently the only FDA-approved medication for children ages 2 years and older with functional constipation and ages 7 years and older with IBS with constipation (IBS-C). The other medications listed are generally approved only for adults and may sometimes be used off-label in pediatric care.
Some studies suggest that these newer medications may improve bowel movements and abdominal pain. However, they may also cause more side effects, including diarrhea and abdominal cramping.
Pushers
These medications work by triggering the colon to contract, and push stool out. They are either derivatives of the senna leaf (Senokot) or alkaloid chemicals such as bisacodyl (e.g., Correctol, Dulcolax). They work faster than mushers but tend to produce more cramps. Stimulant laxatives are important in the treatment of chronic constipation when children no longer feel a bowel movement (BM) or ignore the urge to pass a BM. Stimulant laxatives are safe for long-term use.
Straining and grunting in infants:
Some infants may cry, grunt, or appear uncomfortable when having a bowel movement even when the stool is soft. This is called dyschezia and happens because babies are still learning how to coordinate pushing and relaxing the muscles needed to pass stool. Although it can look concerning, it is usually normal and most babies outgrow it by 4–6 months of age. In this case, laxatives would not help and it not recommended.
Learn more about other general treatments
Adapted from IFFGD Publication: Laxatives: A Parent’s Guide to the Successful Management of Constipation in Children #828 by Joseph Levy, M.D., and Diana Volpert, M.D., Division of Pediatric Gastroenterology, Children’s Hospital of NY-Presbyterian, New York, NY, Colombia University Medical Center; updated by Thomas Wallach M.D., Chief, Pediatric Gastroenterology, SUNY Downstate Health Sciences University; edited by Jose M Garza M.D., Medical director, Neurogastroenterology and Motility, Children’s Healthcare of Atlanta. Partner at Gi Care for Kids, Atlanta, GA.