Stool Softeners Fail to Relieve Chronic Constipation

Patients often arrive in pain, miserable, and desperate for relief from constipation. Defined as fewer than three bowel movements per week lasting more than 4 weeks, chronic constipation affects about 10% of the population.

The goal of those suffering with chronic constipation is simple: to achieve long-term, effective relief. For this, many turn to a popular solution.

“A lot of my [constipated] patients come in taking stool softeners,” said William D. Chey, MD, president-elect of the American College of Gastroenterology (ACG) and chief of the Division of Gastroenterology and Hepatology at the University of Michigan, Ann Arbor, Michigan.

It’s easy to understand the appeal of these over-the-counter options, which are both inexpensive and heavily marketed in catchy commercials. This is reflected in robust sales, projected to grow from $1.82 billion in 2025 to $2.43 billion by 2029.

The problem, according to experts? They don’t work.

Lacking Credible Evidence 

Stool softeners (also known as emollients) act like a surfactant, Chey explained. They increase the amount of water and fat the stool absorbs, softening it to ease passage.

While many of his patients arrive having tried stool softeners, Chey said almost none leave his office still relying on them. Instead, he directs them toward more effective options.

Chey is the co-first author of the latest American Gastroenterological Association (AGA)-ACG guidelines on managing chronic idiopathic constipation (CIC).

“There’s almost no evidence to suggest that so-called stool softeners — the most common of which is docusate sodium (Colace) — do anything for constipation,” Chey told Medscape Medical News. “They’re not recommended in our guidelines, and there’s not credible evidence in support of it.” 

Studies reviewed for the guidelines showed docusate performed no better than placebo and was less effective than psyllium.

In their systematic review of over-the-counter therapies for chronic constipation, Gastroenterologists Darren M. Brenner, MD, FACG, and Satish S.C. Rao, MD, PhD, were unable to even assign stool softeners a grade. There was simply not enough data suggesting they work, Brenner, a professor of medicine and surgery at Northwestern University School of Medicine, Chicago, told Medscape Medical News.

Identifying Better Options

Although stool softeners get a thumbs down from Chey, Brenner, and others, evidence exists for other constipation remedies. In the 2023 AGA-ACG guidelines, an expert panel issued 10 recommendations for the pharmacological management of CIC in adults.

Strong recommendations for treatment of CIC in adults went to:

• Polyethylene glycol (PEG) (GaviLax, GlycoLax, MiraLax)
• Sodium picosulfate (Dulcolax Pico) or bisacodyl (Dulcolax)
• Linaclotide (Linzess)
• Plecanatide (Trulance)
• Prucalopride (Motegrity)

Conditional recommendations were given for:

• Fiber
• Lactulose (Constulose, Kristalose)
• Senna
• Magnesium oxide
• Lubiprostone (Amitiza)

For the first time, magnesium oxide and senna were included as evidence-based treatments. The guidelines also endorsed nonpharmacologic interventions,such as increased fluid intake, dietary fiber, and exercise.

In their updated systematic review of over-the-counter therapies for chronic constipation, Brenner and a colleague identified 1297 studies and evaluated 41 that met inclusion criteria. Stool softeners didn’t make the cut.

PEG and senna showed strong evidence; moderate evidence supported psyllium, SupraFiber, magnesium salts, bisacodyl, sodium picosulfate, and certain fruit-based laxatives (eg, kiwi, mango, prunes, and ficus), as well as yogurt with galacto-oligosaccharide/prunes/linseed oil. Insufficient evidence existed for polydextrose, inulin, and fructo-oligosaccharide.

Surgeons and Their Stool Softeners

“Surgeons love stool softeners,” said Chey, noting how often they appear in post-operative discharge instructions despite a lack of efficacy.

He’s not alone in noticing.

On X, Jennifer Gunter (@Dr.JenGun), an OB/GYN with a robust social media following, once posted: “I’m just a girl, asking people to stop recommending and to stop selling stool softeners.”

Readers chimed in, with one gastroenterologist commenting: “As I always say, worse than placebo!”

While they provide no benefit for CIC, Chey believes stool softeners might offer some efficacy for very mild constipation.

“The good news is, they are really safe,” he said. “There is almost no downside to taking them.”

His advice: “Be familiar with the evidence-based treatments for chronic constipation and stick to those as opposed to using treatments like docusate sodium, which isn’t going to be effective.”

Safety Concerns and Myths About ‘Getting Hooked’

Patients often express fears of “getting hooked” on laxatives. It’s a concern Chey commonly hears. “If I had a nickel for every time a patient said that…”

He encourages patients to consider the opposite risk — leaving constipation untreated could worsen the condition.

“By treating the constipation, it’s very likely that that may prevent them from developing problems over the long term,” Chey said.

He noted that osmotic medications like PEG are generally safe, with limited side effects, and that stimulants are recommended for short-term use (< 4 weeks) or as a rescue therapy.

“For chronic constipation, a lot of people will require laxatives every day, and that’s okay,” Chey said.

Osmotics are supported by longer-term data. PEG is approved by the FDA for occasional constipation treatment, not CIC, but it has been shown to be effective in those with CIC for up to 6 months. Although Chey noted this is a long follow-up period for a constipation study, he has patients who have taken PEG regularly for more than 30 years with no issue.

“There is no silver bullet,” he said. “But all the effective medications make some of the patients better.”

He advised clinicians to choose one treatment from each category recommended in the 2023 AGA-ACG guideline and become familiar with their use.

Taking Patients’ Complaints Seriously

Living with constipation takes a toll on quality of life, many studies have found. According to the AGA-ACG, the impact is on par with conditions such as chronic obstructive pulmonary disease, diabetes, and depression.

Patient complaints shouldn’t be dismissed, experts said.

“Ask a doctor, which is worse, diarrhea or constipation,” Chey said. Many will say diarrhea, citing the severity of the symptoms, but he disagrees. Diarrhea episodes are relatively brief, but people dealing with constipation “feel miserable all day long.”

Or as Brenner put it: “I never poo-poo constipation.”

Chey is a consultant for Ironwood Pharmaceuticals and Ardelyx Pharmaceuticals. Brenner is a consultant for Bayer.

Kathleen Doheny is a freelance journalist in Los Angeles.