Diarrhea octreotide

Somatostatin has a very brief half-life in serum and is not useful clinically. An 8-amino acid analogue with 2 D-amino acids substituted for the naturally occurring L-amino acids is more stable, and monthly injections of a depot form of this analogue (octreotide, Sandostatin LAR) have several uses. Long-acting octreotide is used to treat acromegaly, as described earlier. It is also used to counteract unpleasant effects caused by overproduction of secreted bioactive substances produced by neuroendocrine tumors, including hyperinsulinemia from insulinomas and secretions from carcinoid tumors that cause severe diarrhea. Octreotide may also control severe diarrhea associated with AIDS that has not responded to other treatments. 

USP (Leupton) octreotide ace-tate [79517-01 ] 2H4O2 049 -66 1oOloS2 1019.24 (65) mestastatic carciuoid effects nausea diarrhea loose... 

Diarrhea may occur from effects of chemotherapy on the lower portion of the GI tract. Diarrhea can be severe and may need to be treated with intravenous fluids and electrolytes. Infectious causes, such as C. difficile, should be ruled out. Pharmacologic therapy of diarrhea can range from loperamide or cholestyramine to octreotide for severe cases of diarrhea that are refractory to usual treatments. 

Octreotide -synthetic peptide analogue of somatostatin -abdominal pain, nausea, vomiting, diarrhea -local injection site reactions -cholelithiasis -sweating, flushing -hyperglycemia (many patients will require insulin therapy)... 

Diabetic diarrhea is commonly nocturnal and frequently responds to a 10-to 14-day course of an antibiotic such as doxycycline or metronidazole. Octreotide may be useful in unresponsive cases. 

C. Carcinoid tumors arise from neuroendocrine cells of the gut and secrete serotonin and gastrointestinal hormones, which activate the gastrointestinal tract and result in diarrhea. Most of these tumors have receptors for somatostatin, which inhibit secretion when activated, resulting in reduced activity of the gut. Octreotide is a stable analogue of... 

G. Other applications Octreotide has been reported to be effective in treating noninfectious diarrhea and diarrhea in patients with AIDS, and as an adjunct to endoscopic variceal ligation, to reduce recurrent bleeding from esophageal varices. Micromedex lists many other potential uses. 

Two gastrointestinal neuroendocrine tumors (carcinoid, VIPoma) cause secretory diarrhea and systemic symptoms such as flushing and wheezing. For patients with advanced symptomatic tumors that cannot be completely removed by surgery, octreotide decreases secretory diarrhea and systemic symptoms through inhibition of hormonal secretion and may slow tumor progression. 

Octreotide inhibits intestinal secretion and has dose-related effects on bowel motility. In low doses (50 meg subcutaneously), it stimulates motility, whereas at higher doses (eg, 100-250 meg subcutaneously), it inhibits motility. Octreotide is effective in higher doses for the treatment of diarrhea due to vagotomy or dumping syndrome as well as for diarrhea caused by short bowel syndrome or AIDS. Octreotide has been used in low doses (50 meg subcutaneously) to stimulate small bowel motility in patients with small bowel bacterial overgrowth or intestinal pseudo-obstruction secondary to scleroderma. 

Diarrhea is common soon after starting octreotide but usually resolves within 2 weeks without specific treatment. In a randomized, double-blind, placebo-controlled trial in 203 mostly postmenopausal women with locally recurrent or metastatic breast carcinoma, all of whom were also taking tamoxifen, and who had estrogen-receptor positive and/or progesterone-receptor positive tumors, octreotide was added to the basic treatment in 99 cases (31). The adverse events experienced by 10% or more of the patients and attributed to octreotide were gastrointestinal diarrhea (53%), nausea (16%), and abdominal pain (11%) diarrhea occurred in only 11% of the controls. 

Of 24 patients with hepatocellular carcinoma receiving octreotide LAR, 11 had mild diarrhea (32). The effect of octreotide on bowel transit appears to be variable. In some patients, such as those with carcinoid syndrome, it is useful for the management of diarrhea. 

One of 10 patients with rheumatoid arthritis in an open study stopped using long-acting octreotide because of severe diarrhea and weight loss of 3 kg (34). These effects are dose-related and are similar in healthy volunteers, acromegalic patients, and patients with gastrointestinal tumors (3). 

A 41 year old woman with hepatocellular carcinoma was treated with chemotherapy. Octreotide 100 micrograms bd and LAR 20 mg was added to her therapy to control symptoms of diarrhea, but 10 days later she... 

Beckman RA, Siden R, Yanik GA, Levine JE. Continuous octreotide infusion for the treatment of secretory diarrhea caused by acute intestinal graft-versus-host disease in a child. J Pediatr Hematol Oncol 2000 22(4) 344—50. 

Originally isolated from the hypothalamus, somatostatin is a small polypeptide that is also found in neurons throughout the body, as well as in the intestine and pancreas. Somatostatin therefore predictably has a number of actions. Octreotide [awk TREE oh tide] is a synthetic octapeptide analog of somatostatin. It has a much longer half-life than the natural compound and has found use in the treatment of acromegaly caused by hormone-secreting tumors, and secretory diarrhea associated with tumors producing the vasoactive intestinal peptide (VIP). Adverse effects of octreotide treatment are flatulence, nausea, and steatorrhea. 

Barbounis V, Koumakis G, Vassilomanolakis M, Demiri M, Efremidis AP. Control of irinotecan-induced diarrhea by octreotide after loperamide failure. Support Care Cancer 2001 9(4) 258-60. 

A powerful new synthetic peptide that mimics the action of somatostatin, octreotide acetate (Sandostatin). is approved by the Food and Drug Administration (FDA) for (he treatment of certain rare forms of intestinal endocrine cancers, such as malignant carcinoid tumors and vasoactive intestinal peptide-secreting tumors (VIPomas). Octreotide acetate is indicated for long-term treatment of severe diarrhea associated with these carcinomas. 

Octreotide blocks the release of serotonin and many other active peptides and has been effective in controlling diarrhea and flushing. It is reported to have direct inhibitory effects on intestinal secretion and stimulatory effects on intestinal absorption. Non-gastrin-secreting adenomas of the pancreas are tumors associated with profuse watery diarrhea. This condition has been referred to as Verner-Morrison syndrome, WDHA (watery diarrhea, hypokalemia, and achlorhydria) syndrome, pancreatic cholera, watery diarrhea syndrome, and VIPoma. Excessive secretion of VIP from a retroperitoneal or pancreatic tumor produces most of the clinical features. Excessive VIP is isolated in about half of patients, along with numerous other peptide hormones (peptide histidine methionine [PHM], serotonin,... 

Because octreotide inhibits many other gastrointestinal hormones, it has a variety of intestinal side effects. With prolonged use, gallbladder and biliary tract complications such as cholelithiasis have been reported. About 5% to 10% of patients complain of nausea, diarrhea, and abdominal pain. Local injection pain occurs with about an 8% incidence. With high doses, octreotide may reduce dietary fat absorption, leading to steatorrhea. 

Harris AG, O Dorisio TM, Weltering EA, et al. Consensus statement Octreotide dose titration in secretory diarrhea. Diarrhea Management Conference. Dig Dis Sci 1995 40 1464-1473. 

The most common adverse effects of octreotide therapy are gastrointestinal disturbances such as diarrhea, nausea, abdominal cramps, malabsorption of fat, and flatulence.xhese effects are dose dependent and can be seen within a few hours of the first octreotide injection. Gastrointestinal adverse effects occur in approx-... 

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