Secretin

(BAN, USAN, rINN)
Synonyms: Secretina; Sécrétine; Secretinum; Sekretiini; Sekretin.
Cyrillic synonym: Секретин.

💊 Chemical information

CAS — 17034-35-4 (porcine); 108153-74-8 (human).
ATC — V04CK01.
ATC Vet — QV04CK01.

💊 Units

The potency of secretin may be expressed as Crick-HarperRaper (CHR) units based on the pancreatic secretion in cats or as clinical units, the value of which was amended in the 1960s. One clinical unit is considered to be approximately equivalent to 4 CHR units. One clinical unit is equivalent to 200 nanograms of a purified synthetic preparation of secretin.

💊 Adverse Effects

Hypersensitivity reactions may occasionally occur. Diarrhoea has occurred in patients given high doses by intravenous infusion.

💊 Precautions

The secretin test should be avoided in patients with acute pancreatitis. Patients should receive an intravenous test dose because of the risk of hypersensitivity reactions.

💊 Uses and Administration

Secretin is a polypeptide hormone involved in the regulation of gastric function. It may be prepared from the duodenal mucosa of pigs; synthetic human and porcine versions are also available. On intravenous injection it causes an increase in the secretion by the pancreas of water and bicarbonate into the duodenum. Secretin is used as a diagnostic agent in various disorders of the pancreas. Patients should be given an initial intravenous test dose of 1 clinical unit (200 nanograms); if no hypersensitivity reaction is noted after 1 minute, the diagnostic dose may be given. Secretin is used alone, or with pancreozymin or other cholecystokinetic agents such as ceruletide or sincalide, as a test for exocrine pancreatic function. The test usually involves duodenal intubation of the patient and examination of duodenal aspirate. The diagnostic dose of secretin used has varied but common doses have been 1 clinical unit/kg (200 nanograms/kg) given by slow intravenous injection. Patients with the Zollinger-Ellison syndrome show an increase in gastrin when given secretin; this is in contrast to a small change or no effect in subjects without the disorder. The usual dose of secretin for the diagnosis of Zollinger-Ellison syndrome is 2 clinical units/kg (400 nanograms/kg) by slow intrave nous injection. Serum-gastrin concentrations are measured for up to 30 minutes following the diagnostic dose. Secretin is also used in a dose of 1 clinical unit/kg (200 nanograms/kg) by slow intravenous injection as an aid in the identification of the pancreatic ducts in patients undergoing endoscopic retrograde cholangiopancreatography.

Autism.

There have been anecdotal reports of improvement in behaviour in autistic children given porcine secretin. However, a double-blind placebo-controlled study1 involving 60 children with autism or pervasive developmental disorder noted no benefit over 4 weeks after a single infusion of 400 nanograms/kg of synthetic human secretin. A randomised, placebo-controlled study2 in 64 children with autism has similarly found no evidence of efficacy from 2 repeated doses of porcine secretin. Further controlled studies have likewise failed to demonstrate efficacy.3,4
1. Sandler AD, et al. Lack of benefit of a single dose of synthetic human secretin in the treatment of autism and pervasive developmental disorder. N Engl J Med 1999; 341: 1801–6
2. Roberts W, et al. Repeated doses of porcine secretin in the treatment of autism: a randomized, placebo-controlled trial. Abstract: Pediatrics 2001; 107: e71. Full version: http:// pediatrics.aappublications.org/cgi/content/full/107/5/e71 (accessed 08/07/04
3. Levy SE, et al. Children with autistic spectrum disorders. I: comparison of placebo and single dose of human synthetic secretin. Arch Dis Child 2003; 88: 731–6
4. Coplan J, et al. Children with autistic spectrum disorders. II: parents are unable to distinguish secretin from placebo under double-blind conditions. Arch Dis Child 2003; 88: 737–9.

💊 Preparations

Proprietary Preparations

Ger.: Secrelux; USA: ChiRhoStim; SecreFlo.
Published May 08, 2019.