Secretin.
Research-backed compound with potential health benefits. In a medical setting, it forces your pancreas to release fluids. It's a diagnostic agent.
Reviewed March 2026
- Category
- Compound
What Secretin is, and what it does.
- Does it work
- No. As a supplement, it's worthless and dangerous. The claims from the 90s were proven false in multiple large-scale studies. This is a dead end.
- How much to take
- Zero. You don't take this. A doctor injects a very specific dose based on your body weight (around 0.2 micrograms per kg) for a test.
- Time to feel it
- Given into a vein in a clinical setting, pancreatic fluid output rises within minutes and is collected over about an hour. Swallowed, the peptide is digested, so there is no oral onset.
- The first dose
- Not applicable. The test is over in about an hour in a clinical setting. It's not something you take on your own.
- With regular use
- Not used long-term. It's a one-time injection for a diagnostic test. There are no long-term effects or benefits.
- How well tolerated
- Safe only when administered by a doctor who knows what they're doing. Extremely unsafe otherwise. Don't mess with injectable hormones.
- How it feels
- You feel the injection. Some people feel a brief flushing or mild nausea during the test. That's it. It is not a wellness product.
- The overlooked benefit
- It was the first substance ever called a hormone, described in 1902, and that finding is what established chemical messengers travelling in blood as a category at all.
1 to 2mcg a day is where Secretin works.
Source: Primarily a diagnostic agent. Stuhlman et al., J Pediatr Gastroenterol Nutr, 2004
The proof, claim by claim.
These words describe the research, not the molecule's worth. Research strength is how much work stands behind one claim, and it is never a product score.
Secretin is documented in the library; the clinical read is in the queue. Nothing about the strength of the research prints until the read is done.
- Pancreatic bicarbonate and fluid secretionNarrative review
- Assessment of pancreatic secretory capacityCohort study
- Slowing of gastric emptyingNarrative review
- Reduction of gastrin releaseNarrative review
Questions people ask about Secretin.
- Can I buy Secretin as a supplement?
- No. It's a prescription-only injectable drug. Anything sold online is illegal, fake, and dangerous.
- Does Secretin help with autism?
- No. This was a popular theory 20 years ago that was completely disproven by multiple high-quality clinical trials.
- So what is it actually used for?
- Doctors use it as a diagnostic tool to test how well your pancreas is working.
- Why does it have to be injected?
- It's a peptide hormone. If you swallowed it, your stomach acid would destroy it instantly. It wouldn't do anything.
- Is it 'natural'?
- Your body makes it naturally, yes. But the drug version is a powerful, lab-created compound designed for medical use.
- Are there any supplement alternatives?
- For what goal? If you want digestive support, look at digestive enzymes or probiotics. Secretin is not in that category.
Why these belong in the same formula. Each row says what the basis is, from settled biochemistry through to a trial that measured the pair.
Secretin signals pancreatic duct cells to release bicarbonate, which raises duodenal pH into the range where pancreatic enzymes are active. Pancreatin supplies the enzymes that this pH window makes usable.
Secretin is released by duodenal S cells when acidic chyme arrives from the stomach, and the acid load is the trigger. Betaine hydrochloride raises gastric acidity, which is the upstream stimulus for that release. The relationship runs through normal physiology and is not a claim that a supplement raises circulating secretin to any particular level.
Bicarbonate is what secretin makes the pancreatic ducts secrete, and it is also what neutralises the duodenal acid that triggers the hormone in the first place. Oral bicarbonate raises lumenal pH and so reduces the stimulus. The interaction is a feedback loop rather than an additive effect.
Pancreatic lipase loses activity below roughly pH 4 and is irreversibly denatured at gastric pH. The bicarbonate-rich fluid that secretin drives is what raises duodenal pH into the range where lipase works. That is why enzyme preparations are enteric coated: the coating substitutes for the pH the hormone would otherwise produce.
Bile salts form micelles efficiently only above their critical pH, and conjugated bile acids precipitate in an acidic duodenum. Secretin stimulates bicarbonate and water secretion from biliary as well as pancreatic ductal cells. Fat emulsification therefore depends on the same alkalinising step.
Secretin drives the fluid and bicarbonate arm of the pancreatic response while cholecystokinin drives the enzyme arm, and the two act together on the same gland. A supplemental enzyme blend supplies the enzyme side without the fluid side. The pH environment those enzymes land in is the part secretin governs.
Pepsin needs a strongly acidic stomach and is inactivated as pH rises past about 6. The acid that keeps pepsin working is the same acid that, once it reaches the duodenum, releases secretin and prompts the alkalinising response. The two sit on opposite sides of the pylorus by design.
Calcium carbonate neutralises gastric acid, so less acid reaches the duodenum and the physiological stimulus for secretin release falls. Anything taken for its acid-buffering effect works in the same direction. The point matters for anyone stacking an antacid with acid-dependent digestive aids.
Nothing specific on file for Secretin. Match the label to the daily amount above, and tell your doctor what you take.
Not medical advice. Show the label to your pharmacist.What Secretin actually does.
Secretin is a 27-amino-acid peptide hormone released by S cells of the duodenal and upper jejunal mucosa when acidic chyme lowers lumenal pH below roughly 4.5.
It acts at a class B G protein-coupled receptor on pancreatic and biliary duct cells, raising intracellular cyclic AMP and driving chloride and bicarbonate movement through CFTR, which is what produces the watery alkaline pancreatic juice.
That bicarbonate output neutralises gastric acid arriving in the duodenum and brings lumenal pH into the range where pancreatic enzymes and bile salts function.
Secretin also slows gastric emptying and reduces gastrin release, so the hormone closes the loop on the acid stimulus that released it.
The forms it comes in.
The essence, in one line each.
- On follow-up, exocrine pancreatic function had not returned fully in the group studied; secretin appears in this record as the stimulus used in function testing, not as an intervention.Cohort study. Malecka-Panas et al., 1996 (Materia Medica Polona). PMID 9088129 ↗
- Describes the clinical course followed in a hospital report of impaired exocrine pancreatic function; secretin is named within the report rather than being given as a supplement.Cohort study. Malecka-Panas et al., 1996 (Materia Medica Polona). PMID 9088119 ↗
- Cyclic AMP nanoliposomes were associated with growth, gut development and microbiota measures in broilers; the relevance to secretin is the cAMP second messenger the hormone signals through.Animal study. Chen et al., 2025 (Animals). PMID 40646751 ↗
- Rumen-protected L-tryptophan at graded levels was associated with starch digestion and gastrointestinal hormone measures; gut hormones including secretin appear as measured markers.Animal study. Lee et al., 2025 (Journal of Animal Science and Technology). PMID 39974781 ↗
These are the studies our verdict leans on, chosen from the 4 we read for Secretin. The full linked list is below.
The studies, linked.
12 sources behind our Secretin verdict: peer-reviewed studies and registered clinical trials. Every one links straight to PubMed, the journal, or ClinicalTrials.gov. Read them yourself.
- ClinicalTrials.gov ↗
- Clinical trialA Placebo Controlled, Double-Blind, Parallel, Multicenter Study of Synthetic Human Secretin (ChiRhoStim®) Administered Intravenously to Stimulate Exocrine Pancreas Fluid Secretion for Collection Via Endoscope and Laboratory Analysis of DNA MarkersClinicalTrials.gov ↗PHASE3 · 64 participants · Completed
- Clinical trialPhase 1 Study of the Pancreatic Breath Test to Detect Early Stage Chronic Pancreatitis Utilizing the Secretin Stimulation TestClinicalTrials.gov ↗50 participants · Completed
- ClinicalTrials.gov ↗
- ClinicalTrials.gov ↗
- Clinical trialSecretin Increases Glucose Uptake in Human Brown Adipose Tissue and Induces Satiation.ClinicalTrials.gov ↗PHASE2 · 23 participants · Completed
- Clinical trialSecretin-Stimulated MRCP as an Early Screening Modality for Pancreatic Ductal Abnormalities in Patients at High Risk for Pancreatic Adenocarcinoma: A Pilot StudyClinicalTrials.gov ↗NA · 23 participants · Completed
- Clinical trialEffect of Secretin on Gastric Accommodation, Emptying and Post-nutrient Challenge Symptoms in Functional Dyspepsia and Healthy SubjectsClinicalTrials.gov ↗PHASE1 · 20 participants · Completed
- Clinical trialA Randomised, Double Blind Cross-over Study of Serial MRCP Following Morphine-neostigmine and Secretin Provocation in Healthy VolunteersClinicalTrials.gov ↗PHASE4 · 10 participants · Completed
- Clinical trialRG1068 (Synthetic Human Secretin) Enhanced MRCP for Morphological Evaluation of the Known or Suspected Intraductal Papillary Mucinous Neoplasms of the PancreasClinicalTrials.gov ↗PHASE1 · 2 participants · Terminated
- Clinical trialRG1068 (Synthetic Human Secretin) Enhanced Multidetector CT Pancreatography: Evaluation of the Pancreatic Duct in Patients With Known or Suspected Chronic PancreatitisClinicalTrials.gov ↗PHASE1 · Terminated
- Clinical trialThe Cancer of the Pancreas Screening-5 CAPS5)StudyClinicalTrials.gov ↗PHASE3 · 9,000 participants · Recruiting
Evidence surfaced via Semantic Scholar (Allen Institute for AI) and ClinicalTrials.gov. Ranked by study type and citation weight, not cherry-picked.
Problems people have reported.
Read this carefully. These are 88 voluntary, unverified reactions reported to the FDA (openFDA). The number mostly reflects how popular Secretin is, not how risky it is. A report is not proof Secretin caused anything. It is a signal of what to watch for, nothing more.
Source: openFDA adverse-event reports. Voluntary reporting, not an incidence rate.
FDA Disclaimer: These statements have not been evaluated by the Food and Drug Administration. This information is for educational purposes only and is not intended to diagnose, treat, cure, or prevent any disease. Consult your healthcare provider before starting any supplement regimen.