octreotide

H01CB02

Forms & Strengths

Solution for injection: 50 mcg/mL, 100 mcg/mL, 200 mcg/mL, 500 mcg/mL, 1000 mcg/mL
Depot suspension for injection (LAR): 10 mg, 20 mg, 30 mg

Adult Dosing

Acromegaly (subcutaneous): Initial 50 mcg three times daily; titrate based on GH and IGF-1 levels (usual range 100-300 mcg tid)
Acromegaly (LAR): 20 mg IM every 4 weeks for 3 months, then adjust based on response (range 10-40 mg every 4 weeks)
Carcinoid tumors (subcutaneous): 100-600 mcg/day in 2-4 divided doses
Vasoactive intestinal peptide tumors (VIPomas): 200-300 mcg/day in 2-4 divided doses for first 2 weeks
Bleeding esophageal varices (IV infusion): 25-50 mcg/hour continuous infusion for 2-5 days

Pediatric Dosing

Safety and efficacy in pediatric patients have not been established
Off-label pediatric use for hyperinsulinemic hypoglycemia: 1 to 10 mcg/kg/day subcutaneously divided into 2 to 4 doses

Indications

Reduction of growth hormone and IGF-1 levels in acromegaly inadequate to surgery or radiotherapy
Symptomatic treatment of flushing and diarrhea associated with metastatic carcinoid tumors
Treatment of profuse watery diarrhea associated with vasoactive intestinal peptide-secreting tumors (VIPomas)
Emergency management of bleeding esophageal varices in cirrhosis

Mechanism of Action

Mimics natural somatostatin by binding to somatostatin receptors (principally sst2 and sst5)
Inhibits secretion of growth hormone, serotonin, gastrin, vasoactive intestinal peptide, insulin, glucagon, secretin, and motilin
Reduces splanchnic blood flow and portal pressure

Contraindications

Adverse Reactions

Gastrointestinal: Diarrhea, abdominal pain, nausea, flatulence, constipation, steatorrhea
Endocrine: Hyperglycemia, hypoglycemia, hypothyroidism (with long-term use)
Hepatic/Biliary: Cholelithiasis, biliary sludge, acute hepatitis, jaundice
Cardiovascular: Sinus bradycardia, conduction abnormalities, hypertension
Local: Pain, stinging, or burning at the injection site

Drug Interactions

Cyclosporine: Decreases blood levels of cyclosporine; dose adjustment may be required
Insulin and oral hypoglycemic agents: May alter glycemic control; monitor blood glucose and adjust doses
Beta-blockers and calcium channel blockers: May exacerbate bradycardia; monitor heart rate
Bromocriptine: Increases availability of bromocriptine
Drugs metabolized by CYP450 enzymes: Octreotide may suppress CYP enzymes, altering clearance of co-administered drugs

Curated Content: Needs Vetting Before Put to Clinical Use