Octreotide (Sandostatin) is the longer acting synthetic analogue of the naturally occurring hormone somatostatin. In the hypothalamus it inhibits the release of growth hormone, TSH, prolactin and ACTH. It inhibits the secretion of insulin, glucagon, gastrin and other peptides of the gastro-enteropancreatic system, reducing splanchnic blood flow, portal blood flow, gastrointestinal motility, gastric, pancreatic and small bowel secretion, and increases water and electrolyte absorption.
Indications for use
1. Intestinal obstruction Octreotide decreases the volume of intestinal secretions and thus reduces intestinal distension. It does this by reducing fluid and electrolyte secretion. It also reduces gastrointestinal motility. In patients with cancer and inoperable bowel obstruction octreotide rapidly improves symptoms in approximately 75% of patients.
Octreotide decreases the output from fistulae, occasionally leading to closure of the fistula. It has been used in pancreatic, entero-cutaneous, entero-enteric, entero-vesical, entero-vaginal and tracheo-oesophageal fistulae.
3. Neuroendocrine tumours
Symptoms associated with unresectable hormone secreting tumours eg carcinoid, VIPomas, glucagonomas, gastrinomas, insulinomas.
4. Intractable diarrhoea
Related to high output ileostomies, AIDS, radiation, chemotherapy or bone marrow transplant.
Octreotide is generally administered as either bolus SC or by CSCI
Dose varies according to indication and should be titrated according to effect.
||300 microgram/24hr CSCI
|Hormone secreting tumours: Carcinoid,VIPomas, glucagonomas
||50-100 micrograms tds SC, increasing to 200 micrograms tds
|Intractable diarrhoea / Entero-enteric fistulae
||300 microgram /24 hr
||1500 microgram/24 hr
|Hypertrophic pulmonary osteo-arthropathy
||100 microgram bd SC
||200-600 microgram daily
||600 microgram/24 hr
1. Continuous SC infusion
- Initial starting dose of 100 - 300micrograms/24hrs diluted with 0.9% saline
- Titrate dose according to effect up to maximum recommended dose
- It may take several days before full effect is seen
- It may be possible to reduce the dose if control of symptoms is achieved