Drug information of Secretin

Mechanism of effect

Synthetic human secretin mediates the same biological effects as the naturally-occurring gastrointestinal peptide hormone. Secretin mediates an inhibitory effect on acid secretion by parietal cells of the stomach, and causes alkalinazation of the duodenal content by stimulating the release of pancreatic juice, which has high amounts of water and bicarbonate ions.
Human secretin is a ligand at G-protein coupled secretin receptors which are expressed in the basolateral domain of several tissue cell types, including pancreas, stomach, liver, colon and other tissues. Upon interaction, levels of cAMP increase and initiates the cAMP-mediated signalling cascade that results in phosphorylation of protein kinase A (PKA) and activation of cystic fibrosis transmembrane conductance regulator (CFTR).
Activation of CFTR activates Cl-/HCO3- anion exchanger 2 and leads to secretion of bicarbonate-rich-pancreatic fluid. Via the same cAMP signalling pathway, secretin promotes the secretion of water and electrolytes in cholangiocytes. Secretin may work through vagal-vagal neural pathways since stimulation of the efferent vagus nerve stimulates bicarbonate secretion and atropine blocks secretin-stimulated pancreatic secretion.
Additionally, secretin acts as a diuretic to increase urinary volume and bicarbonate excretion.

Pharmacodynamic

In clinical trials, intravenous administration of synthetic human secretin stimulated the exocrine pancreas to promote juice and bicarbonate secretion, with variable responses depending on the pancreatic function of the individual.

Pharmacokinetics

Half-Life: 45 min

Vd: 2.7 L

Total Body Clearance: 580±51.3 mL/min

Drug indications

• Gastrinoma • Pancreatic exocrine dysfunction

Dosage

Adult

Pancreas Dysfunction

0.2 mcg/kg IV infused over 1 minute

Gastrinoma

0.4 mcg/kg IV infused over 1 minute

Ampulla of Vater & Accessory Papilla

0.2 mcg/kg IV infused over 1 minute

Pediatric

Safety and efficacy not established

Drug contraindications

None

Side effects

nausea , vomiting , flushing , dyspepsia

Interactions

Cyclizine , Meclizine , Esomeprazole , Oxybutynin , Propantheline , Pantoprazole , Trihexyphenidyl , Tolterodine , Scopolamine , Darifenacin , Flavoxate , glycopyrrolate , Trospium , Dexlansoprazole , Lansoprazole , Solifenacin , Atropine , Nizatidine , Benzatropine , Hyoscyamine , Dicyclomine , Dimenhydrinate , Rabeprazole , Ranitidine , Cimetidine , Famotidin , Umeclidinium

methscopolamine

Alerts

Hyporesponse: Coadministration with anticholinergic drugs may cause a hyporesponse to stimulation testing

Hyperresponse: Coadministration of H2-receptor antagonists or PPIs may cause a hyperresponse in gastrin secretion in response to stimulation testing, falsely suggesting gastrinoma

Points of recommendation

• Tell all of your health care providers that you take secretin. This includes your doctors, nurses, pharmacists, and dentists.
• You may need to stop taking some drugs like those that are used to lower stomach acid before getting secretin. Talk with your doctor.
• Tell your doctor if you are pregnant or plan on getting pregnant. You will need to talk about the benefits and risks of using secretin while you are pregnant.
• Tell your doctor if you are breast-feeding. You will need to talk about any risks to your baby.

Pregnancy level

Group c - Not adequate studies in pregnant women