Twenty-four-hour fluid intake and renal handling of electrolytes after various doses of ethanol.

The effects of single ethanol doses on fluid and electrolyte metabolism were studied in 31 male mongrel dogs. The animals were given either 0.75 g/kg 1.50 g/kg, or 2.25 g/kg of a 25% (v/v) ethanol solution or isovolumetric quantities of water. Fluid intake, urine output, and electrolyte (Na, K, Cl, Mg) excretions were measured at 0--3, 3--8, and 8--24 hr. During the ascending portion of the plasma ethanol curve (0--3 hr) there was a diuresis and renal magnesium loss in the two highest dosage ethanol groups. During the initial portion of the descending plasma ethanol curve (3--8 hr), each ethanol group had a significant elevation in voluntary intake. At 8--24 hr, renal retention of sodium, potassium, and chloride was found in the 1.5 and 2.25 g/kg groups, and magnesium excretion was also reduced in the 2.25 g/kg group. Over the 0--24 hr, none of the ethanol groups showed fluid loss, while the 2.25 g/kg ethanol group had significant retention of water. The administration of the 2.25 g/kg ethanol dose also resulted in 24-hr retention of sodium and potassium.