Some claim that LA Sandostatic absorbtion is only 68% and octreotide delivered by pump is more effective. This is not proven, to my knowledge.
Early studies have made this claim. In octreotide LAR drug registration trial, levels were in sub-optimal range for complete receptor saturation. Approximately 40% of patients required the use of “rescue “ medication (subcutaneous aqueous octreotide at doses of 100-500 micrograms three times a day) several days per week.Subcutaneous octreotide is commonly used for “rescue”, for the control of symptoms during early phases of LAR therapy (while blood levels are increasing) and during specific times like pre, intra and post-operatively to prevent carcinoid crisis. For subcutaneous octreotide to be effective it would need to be given as a subcutaneous shot every 4-6 hours. It is claimed that the oscilaltion of levels causes a decrease in effectiveness.When a drug is given by bolus injection, the blood levels rise rapidly, and this is associated with progressive binding of the drug to the cell membrane receptor. When the drug levels fall, the drug comes off the receptor and the drug no longer has an effect.
Continuous subcutaneous infusions of octreotide acetate have been used by some physicians to take advantage of the rapid absorption of octreotide by the subcutaneous tissues. In this scenario the blood levels of octreotide begin to rise when the pump is turned on and continue to do so until the “steady state” is achieved—usually about 2-4 hours. Likewise, following the cessation of the subcutaneous infusion of octreotide, blood levels begin to fall and are back to insignificant levels after 6-8 hours (depending on dose used).
Newer studies have questioned this rationale and comparative study found both methods to be eqivalent. There is no credible emdical evidence that of
LA Sandostatin being inferior to pumps and continuous infusion and I consider the latter to be experimental.
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In vitro modeling of the clinical interactions between octreotide and 111In-pentetreotide: is there evidence of somatostatin receptor downregulation?J Nucl Med. 2006 Feb;47(2):354-9.
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