Postural hypotension: pressor effect of octreotide not mediated by norepinephrine. Orthostatic hypotension of the Shy-Drager syndrome is a chronic incapacitating condition characterized by lack of an appropriate increase in the plasma norepinephrine level in response to standing. Recently, the somatostatin analogue octreotide has been reported to induce a pressor response in patients having this syndrome. We have reported a case of Shy-Drager syndrome in which octreotide was effective, but the rise in blood pressure was not accompanied by an increase in the plasma norepinephrine level. Hence, the pressor effect of octreotide is not mediated by stimulation of the sympathetic nervous system, but probably through splanchnic vasoconstriction. 