Furosemide is a diuretic (water pill) used to treat fluid retention and high blood pressure. Do not take this medication if you are allergic to sulfa medicine. Notify your physician if you are pregnant or nursing. Notify your physician if you have diabetes mellitus. Blood glucose levels may be increased in patients with diabetes mellitus. Take this medication early in the day. Furosemide may be taken with or without food. Take with food or milk if stomach upset occurs. Notify your physician if you develop weakness, cramps, or nausea. Dizziness or lightheadedness may occur with therapy; avoid sudden changes in posture. Furosemide may cause increased sensitivity to sunlight. Use sunscreens and wear protective clothing until degree of sensitivity is determined.
Furosemide may increase the ototoxic potential of aminoglycoside antibiotics, especially in the presence of impaired renal function. Except in life-threatening situations, avoid this combination.
Furosemide should not be used concomitantly with ethacrynic acid because of the possibility of ototoxicity. Patients receiving high doses of salicylates concomitantly with furosemide, as in rheumatic disease, may experience salicylate toxicity at lower doses because of competitive renal excretory sites.
Furosemide has a tendency to antagonize the skeletal muscle relaxing effect of tubocurarine and may potentiate the action of succinylcholine.
Lithium generally should not be given with diuretics because they reduce lithiums renal clearance and add a high risk of lithium toxicity.
Furosemide may add to or potentiate the therapeutic effect of other antihypertensive drugs. Potentiation occurs with ganglionic or peripheral adrenergic blocking drugs.
Furosemide may decrease arterial responsiveness to norepinephrine. However, norepinephrine may still be used effectively.
Simultaneous administration of sucralfate and furosemide tablets may reduce the natriuretic and antihypertensive effects of furosemide. Patients receiving both drugs should be observed closely to determine if the desired diuretic and/or antihypertensive effect of furosemide is achieved. The intake of furosemide and sucralfate should be separated by at least two hours.
Tablets, Injection, and Oral Solution
One study in six subjects demonstrated that the combination of furosemide and acetylsalicylic acid temporarily reduced creatinine clearance in patients with chronic renal insufficiency. There are case reports of patients who developed increased BUN, serum creatinine and serum potassium levels, and weight gain when furosemide was used in conjunction with NSAIDs.
Literature reports indicate that coadministration of indomethacin may reduce the natriuretic and antihypertensive effects of furosemide in some patients by inhibiting prostaglandin synthesis. Indomethacin may also affect plasma renin levels, aldosterone excretion, and renin profile evaluation. Patients receiving both indomethacin and furosemide should be observed closely to determine if the desired diuretic and/or antihypertensive effect of furosemide is achieved.
Furosemide is contraindicated in patients with anuria and in patients with a history of hypersensitivity to furosemide.