Low-molecular-weight polyethylene glycol as a probe of gastrointestinal permeability after alcohol ingestion

Abstract

Gastrointestinal permeability has been assessed previously by the excretion of PEG-400, which consists of inert molecules that are neither degraded nor metabolized and are excreted intact in the urine. We report here the effects of alcohol on gastrointestinal permeability using PEG-400. Ten grams of PEG-400 dissolved in 60 ml of water were given to 12 intoxicated alcoholics (mean blood alcohol: 2406 mg/liter). The mean urinary excretion of PEG-400 in the following 6 hr was 3.75±0.3 gsem. When repeated after sobering up (mean elapsed time: 45 hr), all except one subject showed a decrease in PEG-400 excretion (mean: 2.08±0.2 g) (PPPPP<0.05). The ratio of urea-creatinine clearance and urinary volumes were the same in the three periods. Therefore, PEG-400 excretion was not related to changes in urinary clearance or in volume, since the furosemide increased the volume but not PEG-400 excretion. It is concluded that ethanol increases the permeability of the gastrointestinal tract as measured by the PEG-400 test, both in chronic alcoholics during intoxication and in nonalcoholics after a small dose of ethanol. The permeability alteration is transient once ethanol ingestion stops.