Linaclotide
Linaclotide is the intestinal guanylate cyclase-C agonist in LINZESS. It is used for specified constipation disorders, with different adult and pediatric indications.
At a glance
- Evidence stage
- Approved use
- Regulatory status
- LINZESS is US-approved for adult CIC, IBS-C from age 7, and pediatric functional constipation from age 2 under the May 2026 label.
- Research context
- Linaclotide is the intestinal guanylate cyclase-C agonist in LINZESS. It is used for specified constipation disorders, with different adult and pediatric indications.
What this is
- Linaclotide is the intestinal guanylate cyclase-C agonist in LINZESS. It is used for specified constipation disorders, with different adult and pediatric indications.
What this isn't
- A recommendation to use, prepare, combine, or administer a product
- Evidence that a related molecule or a differently formulated product has the same effects
Key terms
Linaclotide is the intestinal guanylate cyclase-C agonist in LINZESS. It is used for specified constipation disorders, with different adult and pediatric indications.
Linaclotide acts on receptors at the intestinal lining. The resulting cyclic-GMP signal increases chloride and bicarbonate secretion, bringing more fluid into the bowel and accelerating transit. Effects on pain-signaling pathways have also been investigated. Local intestinal activity is the relevant mechanism; it should not be described as systemic tissue repair or microbiome restoration. Product label.
Evidence limits
How to read the evidence
The 2025 FDA label listed functional constipation from age 6; the current May 2026 label and FDA approval record support age 2. This update does not lower the IBS-C age threshold. A response on stool-frequency and pain scales does not prove that every cause of constipation has been treated. Product-specific scope.
Sources appraised 2026-10-28. Educational information; not medical advice. Study findings apply to the populations, preparations and outcomes described.
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