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Orthostatic hypotension is defined as a fall in BP (ie, 30 mm Hg systolic or 10 mm Hg diastolic BP) in response to a postural change from supine to standing. 18 Symptoms include weakness, faintness, dizziness, visual impairment, and even syncope after a change from a lying to a standing posture. Orthostatic hypotension may become disabling, but the BP fall may also be asymptomatic. 19 Orthostatic symptoms can be misjudged as hypoglycemia and can be aggravated by a number of drugs, including vasodilators, diuretics, phenothiazines, and particularly tricyclic antidepressants and insulin. A change from lying to standing normally results in activation of a baroreceptor-initiated, centrally mediated sympathetic reflex, resulting in an increase in peripheral vascular resistance and cardiac acceleration. In patients with diabetes, orthostatic hypotension is usually attributable to damage to the efferent sympathetic …