Linaclotide (Linzess)

FDA-approved context Healing & Recovery 2 sources

Linaclotide is a 14-amino acid synthetic peptide and a potent guanylate cyclase-C (GC-C) agonist. It is FDA-approved for the treatment of irritable bowel syndrome with constipation (IBS-C) and chronic idiopathic constipation (CIC). Research shows it works locally in the gastrointestinal tract to increase fluid secretion and accelerate transit, while also reducing visceral pain.

01Dosing reference

Amount

72 mcg, 145 mcg, or 290 mcg (prescription oral capsule)

Frequency

Once daily, taken on an empty stomach at least 30 minutes before the first meal of the day

Cycle

Continuous daily use as prescribed by a physician

Reference figures, not a recommendationThese values reflect amounts described in the literature and vendor documentation this database indexes. Use the reconstitution calculator to convert them into syringe units.

02Mechanism of action

GC-C Receptor Activation

Linaclotide binds to and activates guanylate cyclase-C (GC-C) receptors on the luminal surface of the intestinal epithelium.

cGMP Elevation

Activation of GC-C leads to increased intracellular and extracellular concentrations of cyclic guanosine monophosphate (cGMP).

Fluid Secretion and Pain Reduction

Intracellular cGMP stimulates secretion of chloride and bicarbonate into the intestinal lumen, increasing fluid and transit. Extracellular cGMP decreases the activity of pain-sensing nerves, reducing visceral pain.

03Human evidence

Significant improvement in bowel habits and abdominal pain in IBS-C patients.

Multiple large-scale, randomized, double-blind, placebo-controlled Phase 3 clinical trials demonstrated efficacy in adults with IBS-C.

Effective in increasing spontaneous bowel movements in chronic idiopathic constipation.

Clinical trials showed sustained improvements in bowel movement frequency and stool consistency in patients with CIC.

04Preclinical evidence

Reduced visceral hyperalgesia in animal models of stress-induced gut pain.

Rodent models demonstrated that linaclotide decreases the firing of colonic sensory nerves, mediating its analgesic effect.

Stimulated fluid secretion without systemic absorption.

In vivo studies showed that linaclotide acts locally in the GI tract with minimal to no systemic bioavailability.

05What is known vs. unknown

Reasonably established

Linaclotide is an FDA-approved prescription medication (Linzess) for IBS-C and CIC.
It acts locally in the gut and has minimal systemic absorption, reducing the risk of systemic side effects.
It effectively increases intestinal fluid secretion and accelerates gastrointestinal transit.
It has a dual mechanism of action, addressing both constipation and visceral abdominal pain.

Unknowns & limits

Long-term safety data beyond the clinical trial periods is still being monitored, though it appears generally safe.
Its efficacy in pediatric populations is not fully established, and it carries a boxed warning against use in young children due to dehydration risk.

06Safety & regulatory context

Regulatory statusLinaclotide is FDA-approved under the brand name Linzess. It is generally well-tolerated, with diarrhea being the most common side effect, which can sometimes be severe. It carries a boxed warning against use in pediatric patients up to 6 years of age due to the risk of serious dehydration, and it should be avoided in patients 6 to 17 years old. It is contraindicated in patients with known or suspected mechanical gastrointestinal obstruction.

07Compared with Plecanatide (Trulance)

Linaclotide (Linzess) vs. Plecanatide (Trulance)

Key difference

Both are GC-C agonists, but plecanatide is an analog of uroguanylin, while linaclotide is structurally related to the heat-stable enterotoxin family.

When researchers discuss each

Researchers discuss linaclotide as the first-in-class GC-C agonist with strong data on pain reduction, while plecanatide is often discussed as a newer alternative with a potentially slightly different side effect profile regarding diarrhea.

08Glossary

Guanylate Cyclase-C (GC-C)

A receptor in the intestines that, when activated, increases fluid secretion and speeds up bowel movements.

cGMP

A signaling molecule inside cells that regulates various physiological processes, including fluid balance and pain signaling in the gut.

Visceral Pain

Pain that originates from the internal organs, such as the intestines, often described as a deep ache or cramping.

09Knowledge check

Q1What is the primary mechanism of action of linaclotide?

Q2Why does linaclotide have minimal systemic side effects?

Q3Which documented limitation of the linaclotide evidence base is explicitly noted in the dossier?

Q4According to the dossier, what structural distinction differentiates linaclotide from plecanatide?

Q5Which of the following safety or regulatory statements about linaclotide is specified in the dossier?

10Sources

More in Healing & Recovery

See all

BPC-157

Healing & Recovery

Early human

BPC-157 is a synthetic peptide sequence based on a protective compound naturally found in human gastric juice. Research suggests it has significant regenerative properties, promoting the healing of tendons, ligaments, muscles, and the gastrointestinal tract by accelerating angiogenesis and modulating growth factors.

250-500 mcg

TB-500 (Thymosin Beta-4)

Healing & Recovery

Early human

TB-500 is a synthetic version of the naturally occurring peptide Thymosin Beta-4. Research indicates it plays a crucial role in tissue repair, wound healing, and reducing inflammation by upregulating actin, a vital protein for cell structure and movement.

2.0 - 2.5 mg per injection

KPV

Healing & Recovery

Early human

KPV (Lys-Pro-Val) is a naturally occurring tripeptide derived from alpha-melanocyte-stimulating hormone (alpha-MSH). Research highlights its potent anti-inflammatory and antimicrobial properties, making it a promising candidate for conditions like inflammatory bowel disease, skin disorders, and wound healing.

200-500 mcg/day

Research and educational use onlyNothing on this site is medical advice, a prescription, or a recommendation for human use. Compounds documented here are research chemicals. Consult a qualified clinician before making any health decision.