CHANGES IN PHARMACOLOGICAL ACTIVITY OF FUROSEMIDE AGAINST THE BACKGROUND OF CHLORAMPHENICOL IN EXPERIMENT

Abstract

THE AIM of the investigation was to establish possible changes of renal effects of a continuous injection of furosemide against the background of permanently preliminarily administered chloramphenicol. MATERIALS AND METHODS. Experiments were performed in rats. The concentration of furosemide collected for 6 and 18 hours after injection was determined using HPLC, sodium and potassium – using the method of flame photometry. RESULTS. A 7 days intraperitoneal injection of furosemide (20) against the background of chloramphenicol (50 mg/kg/day per os) was followed by an increased diuretic effect and less strong weakening of its sodiumuretic effect as compared with experiments without chloramphenicol. The effects obtained were due to an increased renal excretion of the diuretic. The experiments have shown that a continuous injection of the diuretic was not followed by substantial changes of its excretion for the first 6 hours of the day cycle. Excretion of the drug during the following 18 hours was gradually increasing for the whole period of observation. These changes of the diurnal dynamics were responsible for the 1.5 times increased excretion of furosemide with urine which in particular resulted in an increase of its diuretic effect. And more than 85% of the diurnal excretion of sodium took place within the first 6 hours after injection of furosemide and was accompanied by a comparable value of its excretion. Excretion of water and potassium during the day was more even. CONCLUSION. Under conditions of a continuous longterm administration of furosemide against the background of a permanent using of chloramphenicol there occurred 1.5 times greater diurnal excretion of furosemide with urine which gave its substantially increased diuretic effect.