The Effects of Isosorbide on Serum and Cerebrospinal Fluid Osmolality and on the Spinal Fluid Pressure in Man

SOSORBIDE is a dihydric alcohol with a molecular weight of 146, formed by the removal of 2 molecules of water from 1 molecule of sorbitol. We recently reported that orally administered isosorbide lowered cerebrospinal fluid (CSF) pressure in dogs. 9 This paper reports our findings when this osmotic diuretic was administered orally to humans. Methods A dose of 2 gm/kg body weight was chosen as being probably both safe and effective. The 50% isosorbide solutiont was administered via nasogastric tube to comatose patients; conscious cooperative patients drank the iced solution. The CSF pressure was measured with a water manometer attached to a needle in the lumbar subarachnoid space. Osmolality of samples of serum and CSF were determined by the method of freezing point depression.,