A patient who had severe orthostatic hypotension secondary to ingesting Vacor, a rodenticide containing N-3 pyridilmethyl-N'-p-nitrophenyl urea (PNU), fully recovered from this initially disabling condition 11 months after poisoning. Initial treatments with elastic stockings, fludrocortisone acetate, and dihydroergotamine mesylate resulted in no obvious improvement of his orthostasis. Findings from a hemodynamic study performed while the patient was severely orthostatic suggested functional impairment of vascular adrenergic nerve terminals as a major lesion. A similar study after recovery from orthostasis showed that the baroreceptor reflex mechanism returned to normal. This report shows that initially severe and disabling orthostatic hypotension may not be a hopelessly permanent sequela of PNU intoxication and that a gradual, spontaneous full recovery from orthostasis is possible.
(Arch Intern Med 1981;141:1505-1507)