Octreotide can be administered intravenously (IV) or subcutaneously (SQ), as these have equivalent bioavailability. Typically, SQ administration is preferred unless recurrent hypoglycemia necessitates IV infusion.
There is no clear evidence on exact dosing, but most commonly used dosing is as follows:
- Adults: 50-100 mcg SQ every 6 hours for a total of 24 hours; consider infusion of up to 125 mcg/hour IV for recurrent / persistent hypoglycemia.
- Pediatric: 4-5 mcg/kg/day SQ every 6 hours for a total of 24 hours, up to the total adult dose.
When employed, octreotide should be used concomitantly with dextrose infusion or oral carbohydrate supplementation and frequent blood glucose monitoring, although several small studies indicate significant reductions in recurrent hypoglycemic events and in the need for rescue infusions of IV dextrose.
Indications:
Octreotide is a synthetic analog of somatostatin that can be used to treat toxicity from insulin secretagogues, primarily sulfonylureas, and quinine. Octreotide inhibits the release of pancreatic insulin, which prevents hypoglycemia in patients who have overdosed on these medications.
It should be noted that octreotide has not been approved by the US Food and Drug Administration (FDA) for utilization in sulfonylurea-associated hypoglycemia, although many toxicologists recommend its use for refractory hypoglycemia with suspected sulfonylurea toxicity.
FDA-approved uses:
- Treatment of acromegaly
- Treatment of metastatic carcinoid symptoms
- Treatment of vasoactive intestinal secreting tumors
- Treatment of upper gastrointestinal (GI) bleeding
- Treatment of intractable diarrhea
- Treatment of high-output gastroenteropancreatic fistulas
There are no specific contraindications.
Monitoring:
Serial point-of-care glucose levels are necessary to monitor treatment efficacy and to determine whether additional carbohydrates or repeat doses of octreotide are necessary.
It should be noted that, particularly in children, delayed hypoglycemia can occur with intentional or unintentional ingestion of sulfonylurea medications. Observation should be completed for at least 12 hours, although some experts recommend monitoring for 24 hours. Even ingestion of a single adult dose of sulfonylureas may result in hypoglycemia in pediatric patients.
Adverse Effects:
Octreotide is overall well-tolerated, especially at subcutaneous doses under 100 mcg. Above this dose, patients may experience GI symptoms including nausea, abdominal cramping, and/or diarrhea. Some patients also experience light-headedness. Octreotide can also occasionally cause hyperglycemia or injection site pain.
In patients given very high doses of octreotide, up to 120 000 mcg over 8 hours, significant adverse effects were not experienced.
Toxicity:
There have been reports of bradycardia and prolonged QTc interval associated with very long-term use of octreotide in patients with acromegaly, but no reports of toxicity when used as an antidote for sulfonylurea toxicity.
Mechanism of Action:
Octreotide is a synthetic somatostatin analog that also suppresses the secretion of multiple hormones including gastrin, cholecystokinin, growth hormone, glucagon, and insulin.
Mechanism of action specifically in regard to sulfonylurea overdose treatment: Octreotide binds to somatostatin-2 receptors on pancreatic beta cells to prevent calcium influx, which is required for insulin secretion, thereby inhibiting secretion of insulin.