The effect of loop diuretics on the excretion of Na+, Ca2+, Mg2+, and Cl-.

Bumetanide, ethacrynic acid, and furosemide were administered in two equipotent doses to the same five dogs in three separate studies. Intravascular volume was maintained by the replacement of urinary losses. Fractional chloride excretion was used as a marker of diuretic effect. Comparison of absolute and fractional excretion of Na+, Cl-, Ca2+, and Mg2+ did not demonstrate a significant difference among the three diuretics.