Furosemide is injected either intramuscularly or intravenously , usually - mg/kg twice/day, although less before a horse is raced. As with many diuretics, it can cause dehydration and electrolyte imbalance , including loss of potassium , calcium , sodium , and magnesium . Excessive use of furosemide will most likely lead to a metabolic alkalosis due to hypochloremia and hypokalemia . The drug should, therefore, not be used in horses that are dehydrated or experiencing kidney failure. It should be used with caution in horses with liver problems or electrolyte abnormalities. Overdose may lead to dehydration, change in drinking patterns and urination, seizures, gastrointestinal problems, kidney damage, lethargy, collapse, and coma.
Furosemide 40 mg was administered to 8 healthy subjects as an . bolus dose, as 1 tablet in the fasting state, and as 1 tablet and a solution after food intake. The . data gave a total body clearance of 162 +/- ml/min and a renal clearance of 117 +/- ml/min; the volume of distribution at steady state was +/- . Oral administration gave a bio-availability of the tablet (fasting) of 51%. Food intake slightly reduced the bioavailability, but not to a significant extent. There was no significant difference in availability between the tablet and the solution. Moment analysis gave a mean residence time after the . dose, MRTi .v., of 51 +/- min. The mean absorption times (MAT) for all oral doses were significantly longer than the MRTi .v., indicating absorption rate-limited kinetics of furosemide. On average, food delayed the absorption by 60 min. The MAT for the tablet in the postprandial state was significantly longer than for the solution, indicating dissolution rate-limited absorption of the tablet.