Synthetic octapeptide, which is a derivative of the natural hormone somatostatin, dr gerald andriole and has similar pharmacological effects to it, but much longer duration of action.
The drug inhibits deca durabolin pathologically increased secretion of growth hormone (GH) as well as peptides and serotonin produced in the gastro-entero-pancreatic endocrine system. In healthy subjects octreotide, like somatostatin, inhibits GH secretion caused by arginine, exercise and insulin-induced hypoglycemia; insulin secretagogue, glucagon, gastrin peptides and other gastro-entero-pancreatic endocrine systems caused by eating, and the secretion of insulin and glucagon stimulated arginine; TSH secretion caused by thyrotropin-releasing hormone.
Inhibitory effect on GH secretion at octreotide, unlike somatostatin expressed to a greater extent than on insulin secretion. Introduction of octreotide is not accompanied by the phenomenon of hormone hypersecretion by negative feedback.
In patients with acromegaly administration of octreotide provides the vast majority of cases, persistent reduction of GH levels and normalization of the concentration of insulin-like growth factor 1 / somatomedin C (IGF-1).
The majority of patients with acromegaly, octreotide substantially reduces the severity of symptoms such as headache, increased sweating, paresthesia, fatigue, pain in bones and joints, peripheral neuropathy. It has been reported that some patients treated with octreotide pituitary adenomas secreting GH resulted in a decrease in tumor size.
Carcinoid tumors application of octreotide may result in a decrease in severity of disease symptoms, especially such as flushing and diarrhea. In many cases, the clinical improvement accompanied by a reduction in the plasma concentration of serotonin and 5-hydroxyindole excretion acid excretion.
When tumors are characterized by overproduction of vasoactive intestinal peptide (Vipom), the use of octreotide results in most patients to reduce the severe secretory diarrhea, which is characteristic of this condition, which in turn leads to an improvement in the quality of life of the patient. At the same time there is a reduction of concomitant electrolyte imbalance, eg hypokalaemia, dr gerald andriole enabling enteral and parenteral cancel the introduction of fluids and electrolytes. According CT occurs in some patients, slowing or stopping the progression of the tumor, and even the decrease in its size, especially liver metastases. Clinical improvement is usually accompanied by a decrease (up to the normal range) concentrations of vasoactive intestinal peptide (VCSEL) in the plasma.
When Glucagonomas use of octreotide in most cases leads to a marked reduction in necrotizing migratory rash which is characteristic of this condition. Octreotide does not have any significant effect on the severity of diabetes, often observed in Glucagonomas, and typically does not lead to a decrease in the need for insulin or oral hypoglycemic drugs. Patients suffering from diarrhea, octreotide causes its reduction, which is accompanied by an increase in body weight. In the application of octreotide often faster deca durabolin decrease in the plasma concentration of glucagon, but long-term effect of this treatment is not stored. At the same time symptomatic improvement remains stable for a long time.
When gastrinoma / Zollinger-Ellison syndrome, octreotide, used alone or in combination with Hl receptor blockers and proton pump inhibitors, can reduce the formation of hydrochloric acid in the stomach and lead to clinical improvement, including and against diarrhea. It is also possible reduction in the severity and other symptoms possibly related to tumor peptide synthesis, including tides. In some cases, there is a decrease in plasma gastrin concentrations.
Patients with insulinomas reduces octreotide levels of immunoreactive insulin in the blood. In patients with operable tumors, octreotide may provide restoration and maintenance of normoglycemia in the preoperative period. In patients with inoperable benign or malignant tumors, glycemic control may be improved without simultaneously prolonged decline in the level of insulin in the blood.
Patients with rare tumors occurring overproducing releasing factor growth hormone (somatoliberinomami), octreotide reduces the severity of symptoms of acromegaly. This is apparently due to the suppression releasing factor secretion of growth hormone and growth hormone itself. Further reduction may pituitary sizes that before treatment were increased.
After subcutaneous deca durabolin administration of the drug is rapidly and completely absorbed. The time to reach maximum plasma concentration (5.2 mg / ml at a dose of 0.1 mg) – 30 min.Relationship to plasma proteins – 65%, dr gerald andriole with form elements of blood – is extremely small. The volume of distribution is 0.27 l / kg. Total clearance – 160 ml / min. The half-life (T1 / 2) is 100 minutes. Most of the drug is excreted intestine, about 32% is excreted unchanged by the kidneys. After the on / in the elimination is carried out in two phases, T1 / 2 – 10 minutes and 90 minutes respectively. In elderly patients, reduced clearance of octreotide, and T1 / 2 increases. In severe chronic renal clearance is reduced by 2 times.
- Acromegaly (when adequate control of symptoms of the disease is carried out by subcutaneous octreotide reference, in the absence of a sufficient effect of surgery and radiation therapy to prepare for surgery, to treat between courses of radiation therapy to the development of resistant effect in inoperable patients).
- In the treatment of endocrine tumors of the gastrointestinal tract (GIT) and pancreas:
- carcinoid tumors with symptoms of carcinoid syndrome;
- gastrinoma (Zollinger-Ellison syndrome);
- glucagonomas (to control hypoglycemia in the preoperative period, as well as maintenance therapy).
- Somatoliberinomy (tumors characterized by overproduction of growth factor-releasing hormone).
- Prevention of complications after operations on the pancreas; stop bleeding and prevention of rebleeding from esophageal varicose veins in liver cirrhosis (in combination with endoscopic sclerotherapy).
Hypersensitivity to octreotide or other components of the preparation.
Precautions: cholelithiasis, diabetes, pregnancy and lactation.
Pregnancy and lactation
Experience with octreotide in pregnant women is limited. Octreotide should be used during pregnancy only if the expected benefit to the mother outweighs the potential risk to the fetus.
It is not known whether the drug passes into breast milk, therefore caution should be dr gerald andriole exercised when using octreotide for the treatment of nursing mothers.