K’Somatostatin analogue used in carcinoid syndrome, diarrhea and variceal bleeding.
It is an eight amino acid somatostatin analogue that includes the phenylalanine tryptophan-lysine-threonine four amino acid sequence critical receptor binding.
Diminishes VEGF tumor expression.
Octreotide is an octapeptide that mimics natural somatostatin pharmacologically.
Octreotide is a more potent inhibitor of growth hormone, glucagon, and insulin than the natural hormone.
Octreotide has a much longer half-life at about 90 minutes, compared to 2–3 minutes for somatostatin.
Anecdotal evidence that it may help malignant ascites by inhibiting VEGF activity.
Reduces the secretion of many pancreatic and gastrointestinal hormones, prolongs intestinal transit time and can promote absorption of electrolytes.
Approved for treatment for diarrhea associated with metastatic carcinoid tumors and diarrhea associated with vasoactive peptide secreting tumors.
Can control diarrhea caused by 5FU, and is effective in the management of secondary prevention of diarrhea in patients receiving cisplatin (Cascinu)..
Reduces stools in refractory AIDS associated diarrhea (Garcia).
Provides relief for patients with short bowel syndrome (Cooper) and dumping syndrome.
Shown to delay disease progression in patients with previously untreated midgust neurodendocrine tumors.
Probably has low but significant antitumor effects for neuroendocrine tumors but has not undergone randomized trials.
It is most effective to inhibit clinical symptoms related to hypersecretion of ammine and peptides in neuroendocrine tumors.
With carcinoid syndrome it can control diarrhea and flushing in about 40-50% of patients.
Can improve the symptoms of carcinoid in up to 88% of patients (Kvols EK et a).
It may be beneficial in glucagonomas, VIPomas, and to a lesser extent gastrinomas and metastatic insulinomas.
Beneficial for ectopic adrenocorticotropic hormone (ACTH) secretion with Cushing syndrome, ectopic gonadotropin-releasing hormone receptor (GHRH) secretion, oncogenic osteomalacia, and hypercalcemia secondary to ectopic parathyroid hormone related peptide.
Use can result in remission or stabilization of tumor markers such as serotonin and chromogranin-A, in approximately 60-70% of patients.
Common side effects include gall bladder symptoms, hypothyroidism, bradycardia and hyperglycemia.
It is administered subcutaneously at 150 mcg three times a day or intramuscularly 20-30 mg long-acting release on a monthly basis.
Standard Dilutions for intravenous therapy: For up to 200 mcg in 50 ml over 15-30 min.
600 mcg in 250 ml at 25 mcg/hr.
1250 mcg 250 ml 50 mcg/hr.
A synthetic octapeptide that mimics the action of naturally occuring somatostatin and decreases the secretion of gastroenterohepatic peptides that may contribute symptoms in patients with metastatic tumors such as VIPomas.
A potent inhibitor of GH, insulin, and glucagon secretion.
Decreases splanchnic blood flow and inhibits release of serotonin, gastrin, vasoactive intestinal peptide.
Half-life= 1.5hr, which is 30 times greater than natural somatostatin.
Dosing:
To reduce output of GI fistulas: 50 to 200 mcg q8h
Variceal bleeding: 50 mcg bolus followed by 25 to 50 mcg/hr.
AIDS related diarrhea: 100 to 500 mcg SC tid
Short bowel syndrome: 25 mcg/hr infusion or 50 mcg SC bid.
Diarrhea due to chemotherapy: 50 to 100 mcg SC tid
Irritable bowel syndrome: 100 mcg qd to 125 mcg SC bid
Acromegaly: 50 to 100 mcg SC tid
Carcinoid tumors:100-600 mcg in 2-4 divided doses.
VIPomas: 200-300 mcg/day in 2-4 divided doses.
Octreotide is absorbed poorly from the gut, and is therefore administered parenterally: subcutaneously, intramuscularly, or intravenously.
May be administered subcutaneously or intravenously, but subcutaneous injection is the usual route of administration.
Not compatible in Total Parenteral Nutrition (TPN) solutions because of the formation of a glycosyl octreotide conjugate which may decrease the efficacy of the product.
Sandostatin may be diluted in volumes of 50 – 200 mL and infused intravenously over 15-30 minutes or administered by IV push over 3 minutes.
The initial dosage is usually 50 mcg administered twice or three times daily, and upward dose titration is frequently required.
The suggested daily dosage of Sandostatin for carcinoid tumors during the first 2 weeks of therapy ranges from 100-600 mcg/day in 2-4 divided doses.
The median daily maintenance dosage is approximately 450 mcg, but clinical and biochemical benefits were obtained in some patients with as little as 50 mcg.
VIPomas daily dosages of 200-300 mcg in 2-4 divided doses are recommended during the initial 2 weeks of therapy to control symptoms of the disease.
A pilot study suggests intramuscular octreotide slows progression of renal cystic disease.
Octreotide may attenuate renal deterioration in patients with autosomal-dominant polycystic kidney disease.
Administered in NS, D5W
[0 to 200 mcg] [50 ml] [15-30 min]
[600 mcg] [250 ml] [25 mcg/hr]
[1250 mcg] [250 ml] [50 mcg/hr]
Half-life= 1.5hr which is 30 times greater than natural somatostatin.
—Dosing–
Reduce output of GI fistulas: 50 to 200 mcg q8h
Variceal bleeding: 50 mcg bolus f/b 25 to 50 mcg/hr for up to 5days.
AIDS related diarrhea: (prolongs intestinal transit time): 100 to 500 mcg SC tid
Short bowel (ileostomy) syndrome: 25 mcg/hr infusion or 50 mcg SC bid.
Diarrhea due to chemotherapy: 50 to 100 mcg SC tid
Irritable bowel syndrome: 100 mcg qd to 125 mcg SC bid
Acromegaly: 50 to 100 mcg SC tid
Carcinoid tumors:100-600 mcg in 2-4 divided doses.
VIPomas: 200-300 mcg/day in 2-4 divided doses.
Subcutaneous injection is the usual route of administration for control of symptoms.
Pain with subcutaneous administration may be reduced by using the smallest volume that will deliver the desired dose.
I is not compatible in Total Parenteral Nutrition (TPN) solutions because of the formation of a glycosyl octreotide conjugate which may decrease the efficacy of the product.
It may be infused intravenously over 15-30 minutes or administered by IV push over 3 minutes.
The initial dosage is usually 50 mcg administered twice or three times daily.
For acromegaly dosage may be initiated at 50 mcg t.i.d.
The dose most commonly found to be effective is 100 mcg t.i.d..
Some patients with acromegaly require up to 500 mcg t.i.d. for maximum effectiveness.
VIPomas Daily dosages of 200-300 mcg in 2-4 divided doses are recommended during the initial 2 weeks of therapy to control symptoms of the disease.