Orthostatic hypotension.

This article reviews the physiology and pathology of orthostatic blood pressure regulation. It describes the diverse clinical disorders of postural blood pressure adjustment, focusing attention on idiopathic orthostatic hypotension and the Shy-Drager syndrome, with emphasis on clinical aspects, pharmacology, and pathologic anatomy. Proposals are made for the diagnostic evaluation of patients with orthostatic hypotension and for steps to be taken in therapeutic management.