What is the dosage and usage of Sandostatin (octreotide) for conditions like acromegaly and carcinoid syndrome?

Sandostatin (Octreotide) Dosage and Usage

For carcinoid syndrome, start with octreotide 50-100 mcg subcutaneously three times daily, then transition to long-acting octreotide LAR 20-30 mg intramuscularly every 4 weeks once symptoms are stabilized, with short-acting octreotide available for breakthrough symptoms. 1, 2

Carcinoid Syndrome Management

Initial Therapy with Short-Acting Octreotide

• Begin with 50-100 mcg subcutaneously three times daily for symptom control of flushing and diarrhea 1, 2
• Dose can be titrated upward in increments of 50-100 mcg every 8 hours based on symptom response, up to a maximum of 1500 mcg daily 1, 3
• For rapid symptom relief, use 150-250 mcg subcutaneously three times daily 1
• Stabilize patients on short-acting formulation for 10-28 days before converting to long-acting preparations 1

Transition to Long-Acting Formulations

• Standard dosing of octreotide LAR is 20-30 mg intramuscularly every 4 weeks 1
• Therapeutic levels are not achieved for 10-14 days after LAR injection, so continue short-acting octreotide during this overlap period 1, 4
• The 20 mg LAR dose provides optimal control of both flushing and diarrhea based on comparative trials 4
• Dose and frequency may be increased for inadequate symptom control 1
• Short-acting octreotide (150-250 mcg subcutaneously three times daily) can be added for breakthrough symptoms even after LAR initiation 1

Perioperative and High-Risk Situations

• For prevention of carcinoid crisis during surgery or procedures, administer octreotide 50 mcg/hour by continuous IV infusion 1, 5
• Give an initial IV bolus of 50-100 mcg, then start continuous infusion at 50 mcg/hour 1, 5
• Begin prophylaxis 12 hours before the procedure and continue for 24-48 hours afterward 1, 5
• This applies to any stressful intervention including anesthesia, surgical operations, and hepatic artery embolization 1

Acromegaly Management

Dosing Protocol

• Initial dose is 50 mcg subcutaneously three times daily for the first 2 weeks 2
• Maintenance dose ranges from 100-500 mcg three times daily based on GH and IGF-1 suppression 2, 6
• Doses up to 3000 mcg/day have been administered safely in acromegaly patients 6

VIPomas (Watery Diarrhea Syndrome)

Treatment Approach

• Start with 200-300 mcg daily in two to four divided doses during initial 2 weeks 2
• Patients with VIPomas frequently respond dramatically to even small doses with cessation of diarrhea 1
• Titrate dose against vasoactive intestinal peptide levels, targeting normalization 1
• For severe, loperamide-refractory chemotherapy-induced diarrhea, use 500 mcg three times daily subcutaneously 1

Tumor Growth Control

Antiproliferative Indications

• In patients with clinically significant tumor burden or progressive neuroendocrine tumors, initiate octreotide LAR 20-30 mg every 4 weeks 1
• The PROMID study demonstrated median time to tumor progression of 14.3 months with octreotide LAR versus 6.0 months with placebo (P=0.000072) 1
• Stable disease was achieved in 66.7% of patients on octreotide LAR versus 37.2% on placebo at 6 months 1
• For asymptomatic patients with low tumor burden, deferring treatment until progression is also reasonable 1

Other Neuroendocrine Syndromes

Glucagonomas

• Somatostatin analogues improve the characteristic necrolytic migratory erythema rash, though circulating glucagon levels are unlikely to normalize 1
• Only use if syndrome is present; no indication for asymptomatic patients 1

Gastrinomas

• Proton pump inhibitors are first-line therapy; no definite added benefit from somatostatin analogues for symptom control 1
• Some experts advise adding somatostatin analogues, though evidence is limited 1

Insulinomas

• Only 50% of insulinomas express type II somatostatin receptors, limiting efficacy 1
• Diazoxide is preferred first-line therapy for hypoglycemic symptoms 1
• Octreotide has variable effects on blood glucose and may worsen hypoglycemia by suppressing counterregulatory hormones 1

Important Safety Considerations

Monitoring Requirements

• Monitor circulating and urinary hormone levels during treatment 1
• Obtain echocardiogram in carcinoid syndrome patients to assess for carcinoid heart disease, especially if 5-HIAA levels exceed 300 mcmol (57 mg) over 24 hours or if experiencing ≥3 flushing episodes daily 1
• Monitor thyroid function periodically as hypothyroidism may occur 2
• Check glucose levels regularly; both hypoglycemia and hyperglycemia can develop 1, 2

Common Adverse Effects

• Gallbladder abnormalities and cholelithiasis occur frequently; monitor periodically 1, 2
• Fat malabsorption and vitamin A and D malabsorption may develop 1, 5
• Injection site pain, abdominal discomfort, diarrhea, and nausea are common 1, 2
• Sinus bradycardia and cardiac conduction abnormalities may occur; use caution in at-risk patients 2

Critical Pitfall to Avoid

• Never discontinue long-acting somatostatin analogues abruptly before procedures; instead, provide IV octreotide coverage to prevent carcinoid crisis 1
• When using lutetium Lu 177 dotatate, discontinue octreotide at least 24 hours prior to each dose 2

Quality of Life Impact

• Long-acting formulations (LAR and Lanreotide Autogel) demonstrate significant improvement in quality of life compared to multiple daily injections 1
• Patients consistently express preference for monthly intramuscular injections over daily subcutaneous administration 7
• Symptomatic control of flushing and diarrhea is achieved in the majority of patients, with substantial relief even when hormone levels are not fully normalized 1