Quick summary
Secretin is a 27-amino acid gastrointestinal hormone and the first hormone ever discovered (1902). The synthetic form ChiRhoStim is FDA-approved for diagnostic use in exocrine pancreatic function testing, ERCP facilitation, and Zollinger-Ellison syndrome diagnosis, administered as a single IV dose.
Overview
Secretin is a 27-amino acid gastrointestinal hormone produced by S-cells of the duodenum in response to acidic chyme. As the first hormone ever discovered (1902), it stimulates pancreatic bicarbonate secretion and bile flow. ChiRhoStim is the FDA-approved synthetic human secretin used diagnostically for exocrine pancreatic function testing, ERCP facilitation, and Zollinger-Ellison syndrome diagnosis.
Mechanism of action
Secretin binds the secretin receptor (SCTR), a class B GPCR expressed on pancreatic ductal cells, bile duct cells, and gastric mucosa. Receptor activation increases intracellular cAMP via Gs coupling, stimulating pancreatic acinar cells to secrete bicarbonate-rich fluid into the duodenum to neutralize gastric acid. Secretin also inhibits gastrin release, reducing gastric acid secretion. In the liver, it promotes bile bicarbonate secretion. Central actions include modulating satiety and water homeostasis.
Dosing protocols
| Purpose | Route | Dosage | Frequency | Notes |
|---|---|---|---|---|
| pancreatic function test (diagnostic) | intravenous | 0.2–0.4 mcg/kg | single dose (slow IV over 1 minute) | |
| ERCP facilitation | intravenous | 0.2–0.4 mcg/kg | single dose administered before procedure |
Dosing information is for educational purposes only. Consult a qualified healthcare professional before using any peptide.
Research summary
Secretin has over a century of clinical use as a diagnostic agent. The FDA approved ChiRhoStim (synthetic human secretin) for exocrine pancreatic function testing, ERCP facilitation, and Zollinger-Ellison syndrome diagnosis. Exploratory research has investigated secretin in autism spectrum disorder, though results from randomized trials have been inconsistent and it is not approved for this indication. Animal studies suggest roles in neurogenesis and neuroprotection.[1][2][3][4][5]
Evidence grading
Each claimed benefit is graded by the strength of available evidence. Grades reflect study quality, not effect size.
Strong = multiple RCTs · Moderate = limited trials or observational · Preliminary = animal or in vitro only · Insufficient = anecdotal or no published data
Side effects
Side effects vary by individual. This is not an exhaustive list. Report unusual symptoms to a healthcare professional.
Common stacks
Peptides commonly paired with Secretin for synergistic effects.
Legal status
ChiRhoStim (synthetic human secretin) is FDA-approved for diagnostic use via intravenous injection. It is a prescription-only medication. Not approved for therapeutic or off-label self-administration.
Sourcing & access
Prescription required
Secretin is an FDA-approved prescription medication available through licensed healthcare providers, telehealth platforms, and 503A/503B compounding pharmacies.
Frequently asked questions
Secretin is a 27-amino acid GI hormone produced by S-cells of the duodenum in response to acidic chyme. As the first hormone ever discovered in 1902, it stimulates pancreatic bicarbonate secretion and bile flow. ChiRhoStim is the FDA-approved synthetic human secretin.
Secretin binds the secretin receptor (SCTR), a class B GPCR, increasing intracellular cAMP via Gs coupling. This stimulates pancreatic acinar cells to secrete bicarbonate-rich fluid into the duodenum to neutralize gastric acid. It also inhibits gastrin release, promotes bile bicarbonate secretion, and modulates satiety centrally.
ChiRhoStim is FDA-approved and generally well tolerated for diagnostic use. Side effects include flushing, nausea, abdominal discomfort, rare hypotension, and rare allergic reactions. It is administered as a single IV dose under clinical supervision.
ChiRhoStim is FDA-approved for three diagnostic indications: exocrine pancreatic function testing, ERCP facilitation, and Zollinger-Ellison syndrome diagnosis. Exploratory research has investigated secretin in autism spectrum disorder, though randomized trial results have been inconsistent.
Research references
- Secretin: historical perspective and current statusReview
- Secretin: a hormone for HCO3- homeostasisReview
- Effects of secretin gene knockout on the diversity, composition, and function of gut microbiota in adult male micePubMed
- Expression of Secretin and its Receptor Along the Intestinal Tract in Type 2 Diabetes Patients and Healthy ControlsPubMed
- Secretin-enhanced MR Imaging of the PancreasPubMed