FDA approves LINZESS for functional constipation in children 2 to 5 years

The FDA has approved an expanded indication for LINZESS (linaclotide) for pediatric patients aged 2 to 5 years with functional constipation (FC), according to an announcement from Ironwood Pharmaceuticals.¹

The approval broadens the use of the medication, which previously had been approved for pediatric patients aged 6 years and older with FC.² With the expanded indication, LINZESS is now the only FDA-approved prescription therapy for pediatric FC in children aged 2 to 5 years.

Functional constipation is a chronic condition characterized by infrequent or difficult bowel movements that can cause pain and discomfort in children. According to the company, preschool-aged children are commonly affected, with an estimated worldwide prevalence of approximately 3%, although prevalence may vary geographically.

What supported the FDA approval?

The FDA decision was supported by findings from a 12-week phase 3 randomized, placebo-controlled clinical trial that evaluated LINZESS in pediatric patients aged 2 to 5 years with FC. In the study, children who received linaclotide 72 mcg experienced improvement in spontaneous bowel movement frequency compared with placebo.

Investigators also reported that the safety profile observed in younger pediatric patients was generally consistent with the established safety profile previously observed in adults with chronic idiopathic constipation and older pediatric patients with FC.

“Managing functional constipation in young children is especially challenging, as this vulnerable patient population often continues to experience persistent symptoms despite treatment with over-the-counter therapies,” said Julie Khlevner, MD, a pediatric gastroenterologist at Columbia University Vagelos College of Physicians and Surgeons. “Clinicians must carefully balance safety, efficacy and the practical realities of what treatments young children are able and willing to take consistently. The availability of an FDA-approved therapy with an established safety profile expands evidence-based treatment options and may support a more tailored therapeutic approach for children aged 2-5 years. Parents can mix the contents of the LINZESS capsule with applesauce or water, providing flexibility for administration in young children.”

Expanding treatment options in pediatric gastroenterology

Ironwood officials described the expanded pediatric indication as an opportunity to address an unmet need in younger children with chronic constipation symptoms.

“This approval extends the use of LINZESS to younger patients with functional constipation, addressing an important gap in care for this historically underserved population, as reflected by the FDA’s decision to grant priority review,” said Tom McCourt, CEO of Ironwood. “We see this as a natural progression for LINZESS that builds on a well-established safety and efficacy profile to expand the impact of our blockbuster medication in GI care.”

LINZESS, a guanylate cyclase-C agonist, is approved for irritable bowel syndrome with constipation in adults and pediatric patients aged 7 years and older, chronic idiopathic constipation in adults, and FC in pediatric patients aged 2 years and older. The therapy is administered once daily.

According to Ironwood, more than 5.5 million unique patients have received prescriptions for LINZESS since its launch in 2012. The company stated that the medication remains the prescription market leader in the United States for irritable bowel syndrome with constipation and chronic idiopathic constipation.¹

Safety considerations for pediatricians

The prescribing information for LINZESS includes a boxed warning regarding the risk of serious dehydration in pediatric patients younger than 2 years of age. The medication is contraindicated in this population.

The most common adverse reaction associated with LINZESS in both adult and pediatric trials was diarrhea. Severe diarrhea has been reported rarely in pediatric studies. The prescribing information recommends suspending dosing and rehydrating patients if severe diarrhea occurs.

The therapy is also contraindicated in patients with known or suspected mechanical gastrointestinal obstruction.

For pediatricians managing constipation in younger children, the expanded approval provides an FDA-reviewed prescription option for patients who continue to experience symptoms despite dietary modification, behavioral interventions, or over-the-counter treatments.

References

1. Ironwood Pharmaceuticals. FDA Approves Use of LINZESS® (linaclotide) in Pediatric Patients Two Years of Age and Older with Functional Constipation (FC). Ironwood Pharmaceuticals. May 27, 2026. https://investor.ironwoodpharma.com/press-releases/press-release-details/2026/FDA-Approves-Use-of-LINZESS-linaclotide-in-Pediatric-Patients-Two-Years-of-Age-and-Older-with-Functional-Constipation-FC/default.aspx

2. FDA approves first treatment for pediatric functional constipation. U.S. Food and Drug Administration. June 12, 2023. Accessed May 27, 2026. https://www.fda.gov/drugs/news-events-human-drugs/fda-approves-first-treatment-pediatric-functional-constipation?utm_medium=email&utm_source=govdelivery