Basis of nocturnal polyuria in patients with autonomic failure.

Five dysautonomic patients with the Shy-Drager syndrome were studied to determine the basis of their nocturnal polyuria. The results indicated excessive postural modification of renal function in dysautonomic patients. This may, in fact, relate to excessive release of ADH while these patients are up and about, and excessive inhibition while they are recumbent. Treatment with vasopressin produced an inconsistent response.