t be given with diuretics because they reduce lithium’s renal clearance and add a high risk of lithium toxicity. furosemide combined with angiotensin converting enzyme inhibitors or angiotensin ii receptor blockers may lead to severe hypotension and deterioration in renal function, including renal failure. an interruption or reduction in the dosage of furosemide, angiotensin converting enzyme inhibitors, or angiotensin receptor blockers may be necessary. 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. in isolated cases, intravenous administration of furosemide within 24 hours of taking chloral hydrate may lead to flushing, sweating attacks, restlessness, nausea, increase in blood pressure, and tachycardia. use of furosemide concomitantly with chloral hydrate is therefore not recommended. phenytoin interferes directly with renal action of furosemide. methotrexate and other drugs that, like furosemide, undergo significant renal tubular secretion may reduce the effect of furosemide. conversely, furosemide may decrease renal elimination of other drugs that undergo tubular secretion. high-dose treatment of both furosemide and these other drugs may result in elevated serum levels of these drugs and may potentiate their toxicity as well as the toxicity of furosemide. furosemide can increase the risk of cephalosporin-induced nephrotoxicity even in the setting of minor or transient renal impairment. concomitant use of cyclosporine and furosemide is associated with increased risk of gouty arthritis secondary to furosemide-induced hyperuricemia and cyclosporine impairment of renal urate excretion. 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

ycoside antibiotics, ethacrynic acid, or other ototoxic drugs. if the physician elects to use high dose parenteral therapy, controlled intravenous infusion is advisable (for adults, an infusion rate not exceeding 4 mg furosemide per minute has been used) (see precautions, drug interactions ). pediatric use in premature neonates with respiratory distress syndrome, diuretic treatment with furosemide in the first few weeks of life may increase the risk of persistent patent ductus arteriosus (pda), possibly through a prostaglandin-e-mediated process. literature reports indicate that premature infants with post conceptual age (gestational plus postnatal) less than 31 weeks receiving doses exceeding 1 mg/kg/24 hours may develop plasma levels which could be associated with potential toxic effects including ototoxicity. hearing loss in neonates has been associated with the use of furosemide injection (see warnings , above).

uscular fatigue, hypotension, oliguria, tachycardia, arrhythmia or gastrointestinal disturbances such as nausea and vomiting. increases in blood glucose and alterations in glucose tolerance tests (with abnormalities of the fasting and 2-hour postprandial sugar) have been observed, and rarely, precipitation of diabetes mellitus has been reported. in patients with severe symptoms of urinary retention (because of bladder emptying disorders, prostatic hyperplasia, urethral narrowing), the administration of furosemide can cause acute urinary retention related to increased production and retention of urine. thus, these patients require careful monitoring, especially during the initial stages of treatment. in patients at high risk for radiocontrast nephropathy, furosemide can lead to a higher incidence of deterioration in renal function after receiving radiocontrast compared to high-risk patients who received only intravenous hydration prior to receiving radiocontrast. in patients with hypoproteinemia (e.g., associated with nephrotic syndrome) the effect of furosemide may be weakened and its ototoxicity potentiated. asymptomatic hyperuricemia can occur and gout may rarely be precipitated. patients allergic to sulfonamides may also be allergic to furosemide. the possibility exists of exacerbation or activation of systemic lupus erythematosus. as with many other drugs, patients should be observed regularly for the possible occurrence of blood dyscrasias, liver or kidney damage, or other idiosyncratic reactions.

when furosemide is given for prolonged periods, careful clinical observation and laboratory monitoring are particularly advisable (see precautions, laboratory tests ). if the physician elects to use high dose parenteral therapy, add the furosemide to either sodium chloride injection usp, lactated ringer’s injection usp, or dextrose (5%) injection usp after ph has been adjusted to above 5.5, and administer as a controlled intravenous infusion at a rate not greater than 4 mg/min. furosemide injection is a buffered alkaline solution with a ph of about 9 and drug may precipitate at ph values below 7. care must be taken to ensure that the ph of the prepared infusion solution is in the weakly alkaline to neutral range. acid solutions, including other parenteral medications (e.g., labetalol, ciprofloxacin, amrinone, milrinone) must not be administered concurrently in the same infusion because they may cause precipitation of the furosemide. in addition, furosemide injection should not be added to a running intravenous line containing any of these acidic products acute pulmonary edema the usual initial dose of furosemide is 40 mg injected slowly intravenously (over 1 to 2 minutes). if a satisfactory response does not occur within 1 hour, the dose may be increased to 80 mg injected slowly intravenously (over 1 to 2 minutes). if necessary, additional therapy (e.g., digitalis, oxygen) may be administered concomitantl geriatric patients in general, dose selection for the elderly patient should be cautious, usually starting at the low end of the dosing range (see precautions, geriatric use ) pediatric patients parenteral therapy should be used only in patients unable to take oral medication or in emergency situations and should be replaced with oral therapy as soon as practical. the usual initial dose of furosemide injection (intravenously or intramuscularly) in pediatric patients is 1 mg/kg body weight and should be given slowly under close medical supervision. if the diuretic response to the initial dose is not satisfactory, dosage may be increased by 1 mg/kg not sooner than 2 hours after the previous dose, until the desired diuretic effect has been obtained. doses greater than 6 mg/kg body weight are not recommended. literature reports suggest that the maximum dose for premature infants should not exceed 1 mg/kg/day (see warnings, pediatric use ). furosemide injection should be inspected visually for particulate matter and discoloration before administration. to prevent needle-stick injuries, needles should not be recapped, purposely bent, or broken by hand.

tiforme 8. pruritus 4. purpura 9. stevens-johnson syndrome 5. photosensitivity 10. toxic epidermal necrolysis cardiovascular reactions 1. orthostatic hypotension may occur and be aggravated by alcohol, barbiturates or narcotics 2. increase in cholesterol and triglyceride serum levels other reactions 1. hyperglycemia 6. restlessness 2. glycosuria 7. urinary bladder spasm 3. hyperuricemia 8. thrombophlebitis 4. muscle spasms 9. transient injection site pain following intramuscular injection 5. weakness 10. fever whenever adverse reactions are moderate or severe, furosemide dosage should be reduced or therapy withdrawn.

t be given with diuretics because they reduce lithium’s renal clearance and add a high risk of lithium toxicity. furosemide combined with angiotensin converting enzyme inhibitors or angiotensin ii receptor blockers may lead to severe hypotension and deterioration in renal function, including renal failure. an interruption or reduction in the dosage of furosemide, angiotensin converting enzyme inhibitors, or angiotensin receptor blockers may be necessary. 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. in isolated cases, intravenous administration of furosemide within 24 hours of taking chloral hydrate may lead to flushing, sweating attacks, restlessness, nausea, increase in blood pressure, and tachycardia. use of furosemide concomitantly with chloral hydrate is therefore not recommended. phenytoin interferes directly with renal action of furosemide. methotrexate and other drugs that, like furosemide, undergo significant renal tubular secretion may reduce the effect of furosemide. conversely, furosemide may decrease renal elimination of other drugs that undergo tubular secretion. high-dose treatment of both furosemide and these other drugs may result in elevated serum levels of these drugs and may potentiate their toxicity as well as the toxicity of furosemide. furosemide can increase the risk of cephalosporin-induced nephrotoxicity even in the setting of minor or transient renal impairment. concomitant use of cyclosporine and furosemide is associated with increased risk of gouty arthritis secondary to furosemide-induced hyperuricemia and cyclosporine impairment of renal urate excretion. 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

tudy, none of the pregnant rabbits survived an oral dose of 100 mg/kg. data from the above studies indicate fetal lethality that can precede maternal deaths. the results of the mouse study and one of the three rabbit studies also showed an increased incidence and severity of hydronephrosis (distention of the renal pelvis and, in some cases, of the ureters) in fetuses derived from the treated dams as compared with the incidence of fetuses from the control group

dministration is within 5 minutes and somewhat later after intramuscular administration. the peak effect occurs within the first half hour. the duration of diuretic effect is approximately 2 hours. in fasted normal men, the mean bioavailability of furosemide from furosemide tablets and furosemide oral solution is 64% and 60%, respectively, of that from an intravenous injection of the drug. although furosemide is more rapidly absorbed from the oral solution (50 minutes) than from the tablet (87 minutes), peak plasma levels and area under the plasma concentration-time curves do not differ significantly. peak plasma concentrations increase with increasing dose but times-to-peak do not differ among doses. the terminal half-life of furosemide is approximately 2 hours. significantly more furosemide is excreted in urine following the intravenous injection than after the tablet or oral solution. there are no significant differences between the two oral formulations in the amount of unchanged drug excreted in urine. geriatric population furosemide binding to albumin may be reduced in elderly patients. furosemide is predominantly excreted unchanged in the urine. the renal clearance of furosemide after intravenous administration in older healthy male subjects (60 to 70 years of age) is statistically significantly smaller than in younger healthy male subjects (20 to 35 years of age). the initial diuretic effect of furosemide in older subjects is decreased relative to younger subjects (see precautions, geriatric use ).

was questionably positive for sister chromatid exchange. studies on the induction by furosemide of chromosomal aberrations in mice were inconclusive. the urine of rats treated with this drug did not induce gene conversion in saccharomyces cerevisiae . furosemide produced no impairment of fertility in male or female rats, at 100 mg/kg/day (the maximum effective diuretic dose in the rat and 8 times the maximal human dose of 600 mg/day).