Secretin
Secretin hormone
Also ChiRhoStim, Human secretin, Synthetic human secretin, SecreFlo, Porcine secretin, Secretin stimulation test
- Evidence
- BSome human evidence
- FDA status
- FDA approvedas of 2026-10-26
- Route
- Intravenous
- Studies cited
- 2 human0 animal or cell
A hormone used in hospitals to test the pancreas. It works for that, but a trial of 60 children found it did not help autism.
Sold for
Secretin is a century-old hormone used in hospitals to test the pancreas, and briefly, in the late 1990s, hyped as an autism cure.
Studies say
Secretin dependably stimulates pancreatic fluid and gastrin release, which is what its diagnostic approval requires; the randomized trial of secretin for autism found no benefit over placebo.
Why grade B. Secretin is a diagnostic agent whose approval rests on comparative studies showing the synthetic human form produces the same pancreatic and gastrin responses as the porcine hormone it replaced; those studies involved dozens, not hundreds, of patients. The cited randomized trial of secretin as a treatment, in 60 children with autism, was negative. Trial-grade evidence for the diagnostic uses themselves is thin by design. 12
FDA. Synthetic human secretin is FDA-approved as ChiRhoStim (approved 2004) for three diagnostic uses: stimulating pancreatic secretions to diagnose exocrine pancreatic dysfunction, stimulating gastrin release to diagnose gastrinoma, and helping locate the pancreatic duct during ERCP. It is not approved as a treatment for any condition. 2
Written from 2 cited sources. Fact-checked 2026-10-27: 15 claims checked, 4 corrected. Last refreshed 2026-10-27. Not physician reviewed.
What this means for you
- What people take it for
- Testing the pancreas
- Can a US doctor prescribe it?
- Yes, FDA approved for diagnosing pancreas problems and a stomach hormone tumor.
- Properly tested in people?
- Partly: studies of dozens of patients for testing, and a negative autism trial of 60 children.
Evidence checklist
- Randomised controlled trial Autism trial was randomized, n=60yes
- Human study over 100 people Largest trial had 60 childrenno
- More than one research group Autism claim tested and refutedyes
- Clinical outcomes, not surrogate markers Diagnostic test responsesno
- Human safety data beyond case reports Label data, well toleratedyes
Drawn from the cited studies below. A dash means the sources give no information.
What it is
Secretin is a 27-amino-acid hormone released by S cells in the lining of the duodenum when acidic stomach contents arrive. It was the first hormone ever identified, by Bayliss and Starling in 1902, and the word hormone was coined to describe it. Its job is to make the pancreas pour out bicarbonate-rich fluid that neutralizes the acid. 2
Secretin for medical use was for decades extracted from pig intestines. The porcine product went off the market in the late 1990s and was replaced by synthetic forms; synthetic human secretin was approved as ChiRhoStim in 2004 and is now the only secretin product in the United States. It is given intravenously in hospital settings as a diagnostic agent. 2
How it works
Secretin binds receptors on the duct cells of the pancreas, raising cyclic AMP inside them and driving secretion of water and bicarbonate into the pancreatic ducts. A healthy pancreas responds with a brisk rise in fluid volume and bicarbonate concentration; a damaged one, as in chronic pancreatitis, responds weakly, which is the basis of the secretin stimulation test. In the stomach, secretin normally suppresses gastrin release, but gastrin-producing tumors (gastrinomas) respond paradoxically with a sharp rise in gastrin, which makes a secretin injection a specific test for Zollinger-Ellison syndrome. During ERCP, the flood of pancreatic juice helps the endoscopist find the duct opening. 2
What human research shows
The approval studies compared synthetic human secretin with porcine secretin in patients undergoing pancreatic function testing and in patients with known gastrinoma, and found equivalent peak bicarbonate concentrations and equivalent gastrin rises. 2
The autism episode is the best-known trial. After anecdotal reports in 1998 that a child's autism symptoms improved after secretin given for an endoscopy, Sandler and colleagues ran a randomized, double-blind trial in which 60 children aged 3 to 14 with autism or pervasive developmental disorder received a single intravenous dose of synthetic human secretin or saline. Over four weeks secretin was not associated with a significant improvement on any outcome measure; on the Autism Behavior Checklist the placebo group's scores actually fell further (17.8 points against 8.9). Fifty-six children completed the study. The authors noted the follow-up was short and the trial used a single dose, which left room for argument, but no positive controlled trial followed. 1
| Study | Model | Finding |
|---|---|---|
| Sandler 1999, secretin for autism | Humans, n=60 children with autism, randomized, double-blind, placebo-controlled | A single dose of synthetic human secretin produced no significant improvement over saline on any outcome measure over four weeks; 56 of 60 children completed. 1 |
| ChiRhoStim comparative studies (label) | Humans, patients undergoing pancreatic function testing and gastrinoma evaluation | Synthetic human secretin produced pancreatic bicarbonate and gastrin responses equivalent to the porcine hormone it replaced. 2 |
Safety
As a single diagnostic dose, secretin is well tolerated. In a 531-patient open-label trial summarized in the label, the most common reactions were nausea, vomiting, flushing and upset stomach, each in only a few patients. Anticholinergic drugs can blunt the pancreatic response and distort the test result, so they are stopped beforehand. In the autism trial no child had treatment-limiting adverse effects. 12
Questions for your clinician
- Is secretin ever useful for autism?
- Which medicines do I stop before a secretin test?
- What will the test result change?
Questions people ask
What is secretin used for today?
Only diagnosis. It is injected to test how much fluid and bicarbonate the pancreas can produce, to provoke a gastrin spike that unmasks a gastrinoma, and to make the pancreatic duct easier to find during ERCP. 2
Does secretin treat autism?
No. The idea came from anecdotal reports in 1998. A randomized trial of 60 children found no difference from placebo on any behavioral measure. The claim is still repeated on some websites. 1
Why does secretin raise gastrin in gastrinoma but not in healthy people?
In a normal stomach secretin suppresses gastrin-producing cells. Gastrinoma tumor cells carry secretin receptors that respond the opposite way, releasing a burst of gastrin within minutes of the injection. That paradoxical rise is what makes the test specific for Zollinger-Ellison syndrome. 2
Is secretin a peptide you can buy for research or wellness?
Secretin is a prescription diagnostic given intravenously in hospitals, and nothing about it supports a wellness use. There is no published evidence for any benefit outside its diagnostic role, and the one treatment trial, in autism, was negative. 12