The peptide hormone secretin is produced in the duodenum (ChiRhoStim). It promotes the release of fluid from the pancreas that is very bicarbonate-rich. It is injected intravenously to evaluate pancreatic function.

Secretin Uses:

• Diagnosis of gastrinoma:
  • It aids in the diagnosis of gastrinomas and stimulates the release of gastrin.
• Endoscopic retrograde cholangiopancreatography:
  • By inducing pancreatic secretions, it is utilized during endoscopic retrograde cholangiopancreatography to assist in identifying the ampulla of Vater and accessory papilla.
• Diagnosis of pancreatic dysfunction:
  • It is used to assess pancreatic exocrine deficiency by stimulating pancreatic secretions of fluid and bicarbonate.

Secretin Injection (ChiRhoStim) Dose in Adults

Secretin Injection (ChiRhoStim) Dose for Gastrinoma Diagnosis:

• To perform the test, doctors give a dose of secretin through an IV (intravenous injection).
• The typical dose is 0.4 micrograms per kilogram of the patient's body weight, given all at once as a single dose.

Endoscopic retrograde cholangiopancreatography/Secretin Injection (ChiRhoStim) Dose in the Diagnosis of Pancreatic Dysfunction:

• The typical dose for this purpose is 0.2 micrograms per kilogram of body weight, administered intravenously (IV) as a single dose.

Secretin Injection (ChiRhoStim) Dose in Children

As a pancreatic function diagnostic tool, Secretin Injection (ChiRhoStim) Dose:

For diagnosing pancreatic function in infants, children, and adolescents, secretin can be administered as a diagnostic agent.

• Although the data on this use might be limited, one referenced guideline (from Horvath 2016) suggests a dose of 0.2 micrograms per kilogram of body weight.
• This dose should be given intravenously (IV) as a single infusion over a period of 1 minute.

Secretin Injection (ChiRhoStim) Dose in the Gastrinoma (Zollinger-Ellison) Diagnostic Agent:

For the diagnosis of gastrinoma (Zollinger-Ellison syndrome) in adolescents 15 years and older, secretin is used as a diagnostic agent.

• According to the guidance referenced from Berna 2006, the dose is 0.4 micrograms per kilogram of body weight, administered intravenously (IV) as a single dose over 1 minute.
• It’s important to note that this dosing recommendation is based on experiences using the porcine (pig) derived product.
• Additionally, a conversion ratio has been suggested by the manufacturer: 1 unit of the porcine product is equivalent to 0.2 micrograms of the human synthetic secretin product.
• This conversion is crucial for ensuring the correct dosage when using the human synthetic form of secretin, ensuring safety and effectiveness in diagnosing conditions like gastrinoma.

Secretin Injection (ChiRhoStim) Dose to Facilitate Magnetic Resonance Cholangiopancreatography Visualization and Endoscopic Retrograde Cholangiopancreatography:

In infants, children, and adolescents.

• Based on the guidelines from sources like Delaney 2008 and Trout 2013, the recommended dose is 0.2 micrograms per kilogram of body weight.
• This dose should be given intravenously (IV) as a single dose over a period of 1 minute, with a maximum limit of 16 micrograms per dose.

Pregnancy Risk Category: C

• No studies on how secretin might affect animals' ability to reproduce have been done.

Use during breastfeeding:

• It's unclear whether secretin is found in breast milk.
• The manufacturer suggests that when a mother is undergoing secretin therapy, she should consider whether to continue or stop breastfeeding.
• This decision should weigh the potential risk of exposing the infant to the medication against the benefits of breastfeeding for the child and the benefits of the treatment for the mother.

Dose in Kidney Disease:

• The manufacturer's instructions do not include any adjustments to the dosage of secretin for individuals with renal impairment.

Dose in Liver disease:

• The manufacturer's labeling does not include any specific adjustments to the dosage of secretin for individuals with hepatic impairment.

Side Effects of Secretin Injection (ChiRhoStim):

• Gastrointestinal:
  • Nausea
  • vomiting
  • flushing
  • dyspepsia

Contraindications to Secretin Injection (ChiRhoStim):

According to the manufacturer's labeling, there are no listed contraindications for secretin

Warnings and precautions

Hepatic impairment

• In cases of hepatic impairment, it's advised to exercise caution when using secretin, especially in patients with conditions like ethanol-induced liver disease.
• These individuals might react more strongly to secretin stimulation, potentially masking the presence of other pancreatic diseases.
• It's recommended to consider additional testing and clinical assessments alongside secretin administration to aid in accurate diagnosis.

Inflammatory bowel disease

• Patients with inflammatory bowel disease might not respond as expected to secretin stimulation, which could lead to false indications of pancreatic disease.
• In such cases, it's important to consider additional testing and clinical assessments to aid in diagnosis.
• This approach helps ensure that the presence of inflammatory bowel disease does not obscure the accurate evaluation of pancreatic function.

Secretin: Drug Interaction

Monitoring parameters:

Testing Guidelines: Pancreatic Secretion and Serum Gastrin

• Peak Bicarbonate Concentration in Duodenal Fluid Aspirate:
  • This test helps diagnose chronic pancreatitis.
  • Follow specific protocols for collecting pancreatic secretion to ensure accurate results.
• Serum Gastrin Levels:
  • Useful in diagnosing gastrinoma (a type of tumor).
  • Refer to established protocols for collecting blood samples for serum gastrin analysis to ensure reliable results.

How to administer Secretin?

• Method:
  • Administer via intravenous (IV) injection.
  • Inject slowly over a period of 1 minute to ensure proper delivery and minimize potential adverse reactions.

Mechanism of action of Secretin:

• Human secretin is a man-made version of a natural hormone.
• It's produced by cells in the duodenum, which is the first part of the small intestine, in response to increased acidity.
• When secretin is released, it signals the pancreatic ductal cells to produce and release pancreatic fluid.
• This fluid is rich in bicarbonate, which helps neutralize stomach acid entering the small intestine.
• Additionally, secretin might also work through the vagus nerve pathways, where stimulating the efferent vagus nerve can trigger the release of bicarbonate.
• This dual mechanism helps regulate the pH balance in the digestive system.

Distribution:

• Volume of Distribution (V): 2.7 liters
  • This represents the apparent volume in which secretin is distributed throughout the body.

Elimination:

• Half-life (T½) Elimination: 45 minutes
  • Secretin's half-life indicates the time it takes for half of the administered dose to be eliminated from the body.
• Clearance: 580.9 ± 51.3 mL/minute
  • Clearance refers to the rate at which secretin is removed from the bloodstream by elimination processes such as metabolism or excretion.

International Brand Names of Secretin:

• ChiRhoStim
• SecreFlo
• Secrepan
• Secretin Ferring
• Sekretolin

Brand Names in Pakistan:

No Brands Available in Pakistan.