Diuretic action of bumetanide in advanced chronic renal insufficiency.

The effect of bumetanide, a new potent diuretic, was studied in twelve patients with severe chronic renal failure (GFR 2.7 - 10.7 ml/min). Bumetanide 8 mg i.v. caused increased excretion of water and sodium in all patients. In some patients sodium excretion was greater than 50% of filtered load indicating an effect on proximal tubules. Bumetanide 2 mg i.v. was significantly less effective than 8 mg and a greater diuretic effect was produced by bumetanide 16 mg. In a comparative study bumetanide 8 mg was less potent than furosemide 250 mg, a finding in contrast to the potency rate ratio of 1/40 in other conditions. Side effects consisted of mild to moderate muscle pain and stiffness, especially localized in the neck, shoulders and calves. These side effects occurred only in patients with a GFR less than 5.3 ml/min. They were noted in all patients receiving 16 mg and in 3 out of 12 patients who took bumetanide 8 mg. There was no relationship between the occurrence of side effects and plasma bumetanide levels, electrolyte levels or the renal excretion of bumetanide and electrolytes.