(fyoor OH se mide)
Excipient information presented when available (limited, particularly for generics); consult specific product labeling. [DSC] = Discontinued product
Generic: 10 mg/mL (2 mL, 4 mL, 10 mL)
Solution, Injection [preservative free]:
Generic: 10 mg/mL (2 mL, 4 mL, 10 mL)
Generic: 100 mg/100 mL in NaCl 0.9% (100 mL)
Generic: 8 mg/mL (5 mL [DSC], 500 mL); 10 mg/mL (60 mL, 120 mL)
Lasix: 20 mg
Lasix: 40 mg, 80 mg [scored]
Generic: 20 mg, 40 mg, 80 mg
Brand Names: U.S.
- Diuretic, Loop
Inhibits reabsorption of sodium and chloride in the ascending loop of Henle and proximal and distal renal tubules, interfering with the chloride-binding cotransport system, thus causing increased excretion of water, sodium, chloride, magnesium, and calcium
Urine (Oral: 50%, IV: 80%) within 24 hours; feces (as unchanged drug); nonrenal clearance prolonged with renal impairment
Onset of Action
Diuresis: Oral, sublingual: 30 to 60 minutes; IM: 30 minutes; IV: ~5 minutes
Symptomatic improvement with acute pulmonary edema: Within 15 to 20 minutes; occurs prior to diuretic effect
Peak effect: Oral: 1 to 2 hours
Duration of Action
Oral, sublingual: 6 to 8 hours; IV: 2 hours
Normal renal function: 0.5 to 2 hours; End-stage renal disease (ESRD): 9 hours
91% to 99%; primarily to albumin
Use: Labeled Indications
Edema: Management of edema associated with heart failure and hepatic or renal disease; acute pulmonary edema.
Hypertension: Management of hypertension (monotherapy or in combination with other antihypertensives).
Note: According to the Eighth Joint National Committee (JNC 8) guidelines, loop diuretics are not recommended for the initial treatment of hypertension (James 2013). In patients with chronic kidney disease (ie, eGFR <30 mL/minute/1.73 m2), the American Society of Hypertension/International Society of Hypertension (ASH/ISH) suggests that the use of a loop diuretic may be necessary (Weber 2014).
Hypersensitivity to furosemide or any component of the formulation; anuria
Canadian labeling: Additional contraindications (not in US labeling): Hypersensitivity to sulfonamide-derived drugs; complete renal shutdown; hepatic coma and precoma; uncorrected states of electrolyte depletion, hypovolemia, dehydration, or hypotension; jaundiced newborn infants or infants with disease(s) capable of causing hyperbilirubinemia and possibly kernicterus; breast-feeding. Note: Manufacturer labeling for Lasix Special and Furosemide Special Injection also includes: GFR <5 mL/minute or GFR >20 mL/minute; hepatic cirrhosis; renal failure accompanied by hepatic coma and precoma; renal failure due to poisoning with nephrotoxic or hepatotoxic substances.
Note: Although the approved product labeling states this medication is contraindicated with other sulfonamide-containing drug classes, the scientific basis of this statement has been challenged. See “Warnings/Precautions” for more detail.
Note: Oral dose equivalency (approximate) for patients with normal renal function (Brater 1983; Cody 1994; Vargo 1995): Furosemide 40 mg = bumetanide 1 mg = ethacrynic acid 50 mg = torsemide 20 mg
Acute pulmonary edema: IV: Initial: 40 mg/dose. If response not adequate within 1 hour, may increase to 80 mg/dose. Note: Minimal additional response is gained by single doses over 160 to 200 mg; maximum: 200 mg/dose (Brater 1998).
Oral: Initial: 20 to 80 mg/dose; if response is not adequate, may repeat the same dose or increase dose in increments of 20 to 40 mg/dose at intervals of 6 to 8 hours; may titrate up to 600 mg/day with severe edematous states; usual maintenance dose interval is once or twice daily.
Heart failure: Initial: 20 to 40 mg once or twice daily; maximum 600 mg/day (ACCF/AHA [Yancy 2013]). Note: Dosing frequency may be adjusted based on patient-specific diuretic needs.
IM, IV: Initial: 20 to 40 mg/dose; if response is not adequate, may repeat the same dose or increase dose in increments of 20 mg/dose and administer 1 to 2 hours after previous dose (maximum: 200 mg/dose [Brater 1998]). Note: A higher initial dose may be considered for those receiving chronic oral diuretic therapy (the dose of chronic oral therapy may guide the IM/IV dose). Individually determined dose should then be given once or twice daily although some patients may initially require dosing as frequent as every 6 hours.
Continuous IV infusion: Initial: IV bolus dose 40 to 100 mg over 1 to 2 minutes, followed by continuous IV infusion rate of 10 to 40 mg/hour; repeat loading dose before increasing infusion rate (ACCF/AHA [Yancy 2013]); Brater 1998; Howard 2001). Note: In clinical trials evaluating dosing strategies in acute decompensated heart failure, median and maximum doses were ≤ 20 mg/hour (Felker 2011; Triposkidadis 2014). With lower baseline CrCl (eg, CrCl <25 mL/minute), the upper end of the initial infusion dosage range should be considered. If urine output is <1 mL/kg/hour, double as necessary to a maximum of 80 to 160 mg/hour (Howard 2001; Schuller 1997). The risk associated with higher infusion rates (80 to 160 mg/hour) must be weighed against alternative strategies.
Hypertension: Oral: Initial: 40 mg twice daily; individualize according to patient response and use minimal dose necessary to maintain therapeutic response. If response inadequate, may add another antihypertensive. Usual dosage (ASH/ISH [Weber 2014]): 40 mg twice daily.
Ascites, due to cirrhosis (off-label dose): Oral: Initial: 40 mg once daily; titrate every 3 to 5 days as clinically indicated (usual maximum: 160 mg once daily); a furosemide to spironolactone dosing ratio of 40 mg (furosemide) to 100 mg (spironolactone) should be maintained (AASLD [Runyon 2012]).
Oral, IM, IV: Initial: 20 mg/day; increase slowly to desired response.
Note: Oral dose equivalency (approximate) for patients with normal renal function (Brater 1983; Cody 1994; Vargo 1995): Furosemide 40 mg = bumetanide 1 mg = ethacrynic acid 50 mg = torsemide 20 mg
Edema: Infants, Children, and Adolescents:
Oral: Initial: 2 mg/kg/dose increased in increments of 1 to 2 mg/kg/dose with each succeeding dose at intervals of 6 to 8 hours until a satisfactory response is achieved; maximum dose: 6 mg/kg/dose.
IM, IV: Initial: 1 mg/kg/dose; if response not adequate, may increase dose in increments of 1 mg/kg/dose and administer not sooner than 2 hours after previous dose, until a satisfactory response is achieved; may administer maintenance dose at intervals of every 6 to 12 hours; maximum dose: 6 mg/kg/dose.
Hypertension, resistant (off-label use): Children and Adolescents 1 to 17 years: Oral: Initial: 0.5 to 2 mg/kg/dose once or twice daily; maximum dose: 6 mg/kg/dose (AAP 2004).
Dosing: Renal Impairment
Acute renal failure: Doses up to 1 to 3 g daily may be necessary to initiate desired response; avoid use in oliguric states.
Dialysis: Not removed by hemo- or peritoneal dialysis; supplemental dose is not necessary.
Dosing: Hepatic Impairment
Diminished natriuretic effect with increased sensitivity to hypokalemia and volume depletion in cirrhosis. Monitor effects, particularly with high doses.
IV infusion solution may be mixed in NS or D5W solution. May also be diluted for infusion to 1 to 2 mg/mL (maximum: 10 mg/mL).
Parenteral: May administer IM or IV. In adults, undiluted direct IV injections may be administered at a rate of 20 to 40 mg per minute; maximum rate of administration for short-term intermittent infusion is 4 mg/minute; exceeding this rate increases the risk of ototoxicity. In children, a maximum rate of 0.5 mg/kg/minute has been recommended.
Oral: Administer on an empty stomach (Bard 2004). May administer with food or milk if GI distress occurs; however, this may reduce diuretic efficacy.
Note: When IV or oral administration is not possible, the sublingual route may be used. Place 1 tablet under tongue for at least 5 minutes to allow for maximal absorption. Patients should be advised not to swallow during disintegration time (Haegeli 2007).
May cause potassium loss; potassium supplement or dietary changes may be required.
Injection: Store at room temperature. Protect from light. Exposure to light may cause discoloration; do not use furosemide solutions if they have a yellow color. Furosemide solutions are unstable in acidic media, but very stable in basic media. Refrigeration may result in precipitation or crystallization; however, resolubilization at room temperature or warming may be performed without affecting the drug's stability. Infusion solution in D5W, NS, or LR is stable for 24 hours at room temperature.
Tablet, solution: Store at 25°C (77°F); excursions permitted to 15°C to 30°C (59°F to 89°F). Protect from light. Discard opened bottle of solution after 90 days (10 mg/mL concentration only).
Acebrophylline: May enhance the therapeutic effect of Furosemide. Monitor therapy
Ajmaline: Sulfonamides may enhance the adverse/toxic effect of Ajmaline. Specifically, the risk for cholestasis may be increased. Monitor therapy
Alfuzosin: May enhance the hypotensive effect of Blood Pressure Lowering Agents. Monitor therapy
Aliskiren: May decrease the serum concentration of Furosemide. Monitor therapy
Allopurinol: Loop Diuretics may enhance the adverse/toxic effect of Allopurinol. Loop Diuretics may increase the serum concentration of Allopurinol. Specifically, Loop Diuretics may increase the concentration of Oxypurinol, an active metabolite of Allopurinol. Monitor therapy
Amifostine: Blood Pressure Lowering Agents may enhance the hypotensive effect of Amifostine. Management: When amifostine is used at chemotherapy doses, blood pressure lowering medications should be withheld for 24 hours prior to amifostine administration. If blood pressure lowering therapy cannot be withheld, amifostine should not be administered. Consider therapy modification
Aminoglycosides: Loop Diuretics may enhance the adverse/toxic effect of Aminoglycosides. Specifically, nephrotoxicity and ototoxicity. Monitor therapy
Amphetamines: May diminish the antihypertensive effect of Antihypertensive Agents. Monitor therapy
Angiotensin-Converting Enzyme Inhibitors: Loop Diuretics may enhance the hypotensive effect of Angiotensin-Converting Enzyme Inhibitors. Loop Diuretics may enhance the nephrotoxic effect of Angiotensin-Converting Enzyme Inhibitors. Monitor therapy
Antidiabetic Agents: Hyperglycemia-Associated Agents may diminish the therapeutic effect of Antidiabetic Agents. Monitor therapy
Antipsychotic Agents (Second Generation [Atypical]): Blood Pressure Lowering Agents may enhance the hypotensive effect of Antipsychotic Agents (Second Generation [Atypical]). Monitor therapy
Barbiturates: May enhance the hypotensive effect of Blood Pressure Lowering Agents. Monitor therapy
Benperidol: May enhance the hypotensive effect of Blood Pressure Lowering Agents. Monitor therapy
Beta2-Agonists: May enhance the hypokalemic effect of Loop Diuretics. Monitor therapy
Bilastine: Loop Diuretics may enhance the QTc-prolonging effect of Bilastine. Monitor therapy
Bile Acid Sequestrants: May decrease the absorption of Loop Diuretics. Consider therapy modification
Brigatinib: May diminish the antihypertensive effect of Antihypertensive Agents. Brigatinib may enhance the bradycardic effect of Antihypertensive Agents. Monitor therapy
Brimonidine (Topical): May enhance the hypotensive effect of Blood Pressure Lowering Agents. Monitor therapy
Bromperidol: Blood Pressure Lowering Agents may enhance the hypotensive effect of Bromperidol. Bromperidol may diminish the hypotensive effect of Blood Pressure Lowering Agents. Avoid combination
Cabozantinib: MRP2 Inhibitors may increase the serum concentration of Cabozantinib. Monitor therapy
Canagliflozin: May enhance the hypotensive effect of Loop Diuretics. Management: If canagliflozin is combined with a loop diuretic, monitor for symptoms of intravascular volume depletion and hypotension. Canadian product labeling recommends avoiding the combination of canagliflozin and loop diuretics. Consider therapy modification
Cardiac Glycosides: Loop Diuretics may enhance the adverse/toxic effect of Cardiac Glycosides. Specifically, cardiac glycoside toxicity may be enhanced by the hypokalemic and hypomagnesemic effect of loop diuretics. Monitor therapy
Cefazedone: May enhance the nephrotoxic effect of Loop Diuretics. Monitor therapy
Cefotiam: Loop Diuretics may enhance the nephrotoxic effect of Cefotiam. Monitor therapy
Cefpirome: Loop Diuretics may enhance the nephrotoxic effect of Cefpirome. Monitor therapy
Ceftizoxime: Loop Diuretics may enhance the nephrotoxic effect of Ceftizoxime. Monitor therapy
Cephalothin: Loop Diuretics may enhance the nephrotoxic effect of Cephalothin. Monitor therapy
Cephradine: May enhance the nephrotoxic effect of Loop Diuretics. Monitor therapy
Chloral Betaine: Furosemide may enhance the adverse/toxic effect of Chloral Betaine. Consider therapy modification
Chloral Hydrate: Furosemide may enhance the adverse/toxic effect of Chloral Hydrate. Avoid combination
CISplatin: Loop Diuretics may enhance the nephrotoxic effect of CISplatin. Loop Diuretics may enhance the ototoxic effect of CISplatin. Monitor therapy
Corticosteroids (Orally Inhaled): May enhance the hypokalemic effect of Loop Diuretics. Monitor therapy
Corticosteroids (Systemic): May enhance the hypokalemic effect of Loop Diuretics. Monitor therapy
CycloSPORINE (Systemic): May enhance the adverse/toxic effect of Loop Diuretics. Monitor therapy
Desmopressin: Loop Diuretics may enhance the hyponatremic effect of Desmopressin. Avoid combination
Diacerein: May enhance the therapeutic effect of Diuretics. Specifically, the risk for dehydration or hypokalemia may be increased. Monitor therapy
Diazoxide: May enhance the hypotensive effect of Blood Pressure Lowering Agents. Monitor therapy
Dofetilide: Loop Diuretics may enhance the QTc-prolonging effect of Dofetilide. Monitor therapy
DULoxetine: Blood Pressure Lowering Agents may enhance the hypotensive effect of DULoxetine. Monitor therapy
Empagliflozin: May enhance the hypotensive effect of Loop Diuretics. Monitor therapy
Ethacrynic Acid: Furosemide may enhance the ototoxic effect of Ethacrynic Acid. Avoid combination
Foscarnet: Loop Diuretics may increase the serum concentration of Foscarnet. Consider therapy modification
Fosphenytoin: May diminish the diuretic effect of Loop Diuretics. Monitor therapy
Herbs (Hypertensive Properties): May diminish the antihypertensive effect of Antihypertensive Agents. Monitor therapy
Herbs (Hypotensive Properties): May enhance the hypotensive effect of Blood Pressure Lowering Agents. Monitor therapy
Hypotension-Associated Agents: Blood Pressure Lowering Agents may enhance the hypotensive effect of Hypotension-Associated Agents. Monitor therapy
Ipragliflozin: May enhance the adverse/toxic effect of Loop Diuretics. Specifically, the risk for intravascular volume depletion may be increased. Monitor therapy
Ivabradine: Loop Diuretics may enhance the arrhythmogenic effect of Ivabradine. Monitor therapy
Levodopa: Blood Pressure Lowering Agents may enhance the hypotensive effect of Levodopa. Monitor therapy
Levosulpiride: Loop Diuretics may enhance the adverse/toxic effect of Levosulpiride. Avoid combination
Licorice: May enhance the hypokalemic effect of Loop Diuretics. Monitor therapy
Lithium: Loop Diuretics may decrease the serum concentration of Lithium. Loop Diuretics may increase the serum concentration of Lithium. Monitor therapy
Lormetazepam: May enhance the hypotensive effect of Blood Pressure Lowering Agents. Monitor therapy
Mecamylamine: Sulfonamides may enhance the adverse/toxic effect of Mecamylamine. Avoid combination
Methotrexate: May diminish the therapeutic effect of Loop Diuretics. Loop Diuretics may increase the serum concentration of Methotrexate. Methotrexate may increase the serum concentration of Loop Diuretics. Management: Monitor for increased methotrexate and/or loop diuretic levels/toxicity with concomitant use of these agents and monitor for decreased therapeutic effects of loop diuretics. Methotrexate and/or loop diuretic dose reductions may be necessary. Consider therapy modification
Methylphenidate: May diminish the antihypertensive effect of Antihypertensive Agents. Monitor therapy
Molsidomine: May enhance the hypotensive effect of Blood Pressure Lowering Agents. Monitor therapy
Naftopidil: May enhance the hypotensive effect of Blood Pressure Lowering Agents. Monitor therapy
Neuromuscular-Blocking Agents: Loop Diuretics may diminish the neuromuscular-blocking effect of Neuromuscular-Blocking Agents. Loop Diuretics may enhance the neuromuscular-blocking effect of Neuromuscular-Blocking Agents. Monitor therapy
Nicergoline: May enhance the hypotensive effect of Blood Pressure Lowering Agents. Monitor therapy
Nicorandil: May enhance the hypotensive effect of Blood Pressure Lowering Agents. Monitor therapy
Nitroprusside: Blood Pressure Lowering Agents may enhance the hypotensive effect of Nitroprusside. Monitor therapy
Nonsteroidal Anti-Inflammatory Agents: May diminish the diuretic effect of Loop Diuretics. Loop Diuretics may enhance the nephrotoxic effect of Nonsteroidal Anti-Inflammatory Agents. Management: Monitor for evidence of kidney injury or decreased therapeutic effects of loop diuretics with concurrent use of an NSAID. Consider avoiding concurrent use in CHF or cirrhosis. Concomitant use of bumetanide with indomethacin is not recommended. Consider therapy modification
Obinutuzumab: May enhance the hypotensive effect of Blood Pressure Lowering Agents. Management: Consider temporarily withholding blood pressure lowering medications beginning 12 hours prior to obinutuzumab infusion and continuing until 1 hour after the end of the infusion. Consider therapy modification
Opioid Analgesics: May enhance the adverse/toxic effect of Diuretics. Opioid Analgesics may diminish the therapeutic effect of Diuretics. Monitor therapy
Pentoxifylline: May enhance the hypotensive effect of Blood Pressure Lowering Agents. Monitor therapy
Phenytoin: May diminish the diuretic effect of Loop Diuretics. Monitor therapy
Pholcodine: Blood Pressure Lowering Agents may enhance the hypotensive effect of Pholcodine. Monitor therapy
Phosphodiesterase 5 Inhibitors: May enhance the hypotensive effect of Blood Pressure Lowering Agents. Monitor therapy
Probenecid: May enhance the adverse/toxic effect of Loop Diuretics. Probenecid may diminish the diuretic effect of Loop Diuretics. Probenecid may increase the serum concentration of Loop Diuretics. Management: Monitor for decreased diuretic effects or increased adverse effects of loop diuretics with concomitant use of probenecid. Bumetanide prescribing information recommends against concomitant use of probenecid. Monitor therapy
Promazine: Loop Diuretics may enhance the QTc-prolonging effect of Promazine. Avoid combination
Prostacyclin Analogues: May enhance the hypotensive effect of Blood Pressure Lowering Agents. Monitor therapy
Quinagolide: May enhance the hypotensive effect of Blood Pressure Lowering Agents. Monitor therapy
Reboxetine: May enhance the hypokalemic effect of Loop Diuretics. Monitor therapy
RisperiDONE: Loop Diuretics may enhance the adverse/toxic effect of RisperiDONE. Management: Consider alternative diuretic therapy (e.g., thiazides) to more potent diuretics (e.g., furosemide) in elderly patients receiving risperidone. Patients who require use of more potent diuretic therapy should be closely monitored and adequately hydrated. Consider therapy modification
Salicylates: May diminish the diuretic effect of Loop Diuretics. Loop Diuretics may increase the serum concentration of Salicylates. Monitor therapy
Sodium Phosphates: Diuretics may enhance the nephrotoxic effect of Sodium Phosphates. Specifically, the risk of acute phosphate nephropathy may be enhanced. Management: Consider avoiding this combination by temporarily suspending treatment with diuretics, or seeking alternatives to oral sodium phosphate bowel preparation. If the combination cannot be avoided, hydrate adequately and monitor fluid and renal status. Consider therapy modification
Sucralfate: May decrease the serum concentration of Furosemide. Sucralfate may impair the absorption of furosemide. Management: Avoid concomitant oral administration of furosemide and sucralfate. Separate administration by at least 2 hours. Does not apply to parenterally administered furosemide. Consider therapy modification
Teriflunomide: May increase the serum concentration of OAT3 Substrates. Monitor therapy
Tobramycin (Oral Inhalation): Loop Diuretics may enhance the nephrotoxic effect of Tobramycin (Oral Inhalation). Loop Diuretics may enhance the ototoxic effect of Tobramycin (Oral Inhalation). Monitor therapy
Topiramate: Loop Diuretics may enhance the hypokalemic effect of Topiramate. Monitor therapy
Xipamide: May enhance the adverse/toxic effect of Loop Diuretics. Specifically, the risk of hypovolemia, electrolyte disturbances, and prerenal azotemia may be increased. Monitor therapy
Yohimbine: May diminish the antihypertensive effect of Antihypertensive Agents. Monitor therapy
May lead to false-negative aldosterone/renin ratio (ARR) (Funder 2016).
Frequency not defined:
Cardiovascular: Necrotizing angiitis, orthostatic hypotension, thrombophlebitis, vasculitis
Central nervous system: Dizziness, headache, paresthesia, restlessness, vertigo
Dermatologic: Acute generalized exanthematous pustulosis, bullous pemphigoid, erythema multiforme, exfoliative dermatitis, pruritus, skin photosensitivity, skin rash, Stevens-Johnson syndrome, toxic epidermal necrolysis, urticaria
Endocrine & metabolic: Glycosuria, hyperglycemia, hyperuricemia, increased serum cholesterol, increased serum triglycerides
Gastrointestinal: Abdominal cramps, anorexia, constipation, diarrhea, gastric irritation, mouth irritation, nausea, pancreatitis, vomiting
Genitourinary: Bladder spasm
Hematologic & oncologic: Agranulocytosis, anemia, aplastic anemia, eosinophilia, hemolytic anemia, leukopenia, purpura, thrombocytopenia
Hepatic: Hepatic encephalopathy, intrahepatic cholestatic jaundice, liver enzymes increased
Hypersensitivity: Anaphylaxis, anaphylactoid reaction, anaphylactic shock
Immunologic: DRESS syndrome
Local: Pain at injection site (following IM injection)
Neuromuscular & skeletal: Muscle spasm, weakness
Ophthalmic: Blurred vision, xanthopsia
Otic: Deafness, tinnitus
Renal: Interstitial nephritis (allergic), renal disease
Concerns related to adverse effects:
• Fluid/electrolyte loss: [US Boxed Warning]: If given in excessive amounts, furosemide, similar to other loop diuretics, can lead to profound diuresis, resulting in fluid and electrolyte depletion. Close medical supervision and dose evaluation are required. Watch for and correct electrolyte disturbances; adjust dose to avoid dehydration. When electrolyte depletion is present, therapy should not be initiated unless serum electrolytes, especially potassium, are normalized. Risk of hypokalemia may be increased by: rapid diuresis, poor oral potassium intake, cirrhosis, and combined use with large amounts of licorice, corticosteroids, or laxatives (chronic use). In contrast to thiazide diuretics, a loop diuretic can also lower serum calcium concentrations. Electrolyte disturbances can predispose a patient to serious cardiac arrhythmias.
• Hyperuricemia: Asymptomatic hyperuricemia has been reported with use; rarely, may precipitate gout.
• Nephrotoxicity: Monitor fluid status and renal function in an attempt to prevent oliguria, azotemia, and reversible increases in BUN and creatinine; close medical supervision of aggressive diuresis required. May increase risk of radiocontrast-induced nephropathy in high-risk patients.
• Ototoxicity: Rapid IV administration, severe renal impairment, excessive doses, hypoproteinemia, and concurrent use of other ototoxins is associated with ototoxicity.
• Photosensitivity: Photosensitization may occur.
• Sulfonamide (“sulfa”) allergy: The approved product labeling for many medications containing a sulfonamide chemical group includes a broad contraindication in patients with a prior allergic reaction to sulfonamides. There is a potential for cross-reactivity between members of a specific class (eg, two antibiotic sulfonamides). However, concerns for cross-reactivity have previously extended to all compounds containing the sulfonamide structure (SO2NH2). An expanded understanding of allergic mechanisms indicates cross-reactivity between antibiotic sulfonamides and nonantibiotic sulfonamides may not occur or at the very least this potential is extremely low (Brackett 2004; Johnson 2005; Slatore 2004; Tornero 2004). In particular, mechanisms of cross-reaction due to antibody production (anaphylaxis) are unlikely to occur with nonantibiotic sulfonamides. T-cell-mediated (type IV) reactions (eg, maculopapular rash) are less well understood and it is not possible to completely exclude this potential based on current insights. In cases where prior reactions were severe (Stevens-Johnson syndrome/TEN), some clinicians choose to avoid exposure to these classes.
• Thyroid effects: Doses >80 mg may result in transient increase in free thyroid hormones, followed by an overall decrease in total thyroid hormone levels.
• Adrenal insufficiency: Avoid use of diuretics for treatment of elevated blood pressure in patients with primary adrenal insufficiency (Addison disease). Adjustment of glucocorticoid/mineralocorticoid therapy and/or use of other antihypertensive agents is preferred to treat hypertension (Bornstein 2016; Inder 2015).
• Cirrhosis: In cirrhosis, avoid electrolyte and acid/base imbalances that might lead to hepatic encephalopathy; correct electrolyte and acid/base imbalances prior to initiation when hepatic coma is present. Supplemental potassium or an aldosterone antagonist, when appropriate, may reduce risk of hypokalemia and metabolic alkalosis. Close monitoring warranted, especially with initiation of therapy.
• Diabetes: Use with caution in patients with prediabetes or diabetes mellitus; may see a change in glucose control.
• Prostatic hyperplasia/urinary stricture: May cause urinary retention due to increased urine production, especially upon initiation of therapy.
• Systemic lupus erythematosus (SLE): May cause SLE exacerbation or activation.
Concurrent drug therapy issues:
• Drug-drug interactions: Potentially significant interactions may exist, requiring dose or frequency adjustment, additional monitoring, and/or selection of alternative therapy. Consult drug interactions database for more detailed information.
• Pediatric: May lead to nephrocalcinosis or nephrolithiasis in premature infants or in children <4 years of age with chronic use. May prevent closure of patent ductus arteriosus in premature infants.
• Surgical patients: If given the morning of surgery, furosemide may render the patient volume depleted and blood pressure may be labile during general anesthesia.
Dosage form specific issues:
• Propylene glycol: Some dosage forms may contain propylene glycol; large amounts are potentially toxic and have been associated hyperosmolality, lactic acidosis, seizures, and respiratory depression; use caution (AAP 1997; Zar 2007).
Other warnings and precautions:
• Diuretic resistance: For some patients, despite higher doses of loop diuretic treatment, an adequate diuretic response cannot be attained. Diuretic resistance can usually be overcome by intravenous administration, the use of two diuretics together (eg, furosemide and chlorothiazide), or the use of a diuretic with a positive inotropic agent. When such combinations are used, serum electrolytes need to be monitored even more closely (ACC/AHA [Yancy 2013]; Cody 1994; HFSA 2010).
Monitor I & O (inpatient setting) and weight daily; blood pressure, orthostasis; serum electrolytes, renal function; monitor hearing with high doses or rapid IV administration
Pregnancy Risk Factor
Adverse events have been observed in animal reproduction studies. Furosemide crosses the placenta (Riva 1978). Furosemide has been used to treat heart failure in pregnant women (ESC 2011; Johnson-Coyle 2012). Monitor fetal growth if used during pregnancy; may increase birth weight.
• Discuss specific use of drug and side effects with patient as it relates to treatment. (HCAHPS: During this hospital stay, were you given any medicine that you had not taken before? Before giving you any new medicine, how often did hospital staff tell you what the medicine was for? How often did hospital staff describe possible side effects in a way you could understand?)
• Patient may experience constipation, diarrhea, nausea, vomiting, or headache. Have patient report immediately to prescriber signs of fluid and electrolyte problems (mood changes, confusion, muscle pain or weakness, abnormal heartbeat, severe dizziness, passing out, tachycardia, increased thirst, seizures, loss of strength and energy, lack of appetite, urinary retention or change in amount of urine passed, dry mouth, dry eyes, nausea, or vomiting), signs of high blood sugar (confusion, fatigue, increased thirst, increased hunger, polyuria, flushing, fast breathing, or breath that smells like fruit), signs of liver problems (dark urine, fatigue, lack of appetite, nausea, abdominal pain, light-colored stools, vomiting, or jaundice), signs of pancreatitis (severe abdominal pain, severe back pain, severe nausea, or vomiting), severe dizziness, passing out, burning or numbness feeling, urinary retention, change in amount of urine passed, loss of strength and energy, bruising, bleeding, chills, pharyngitis, tinnitus, or hearing impairment (HCAHPS).
• Educate patient about signs of a significant reaction (eg, wheezing; chest tightness; fever; itching; bad cough; blue skin color; seizures; or swelling of face, lips, tongue, or throat). Note: This is not a comprehensive list of all side effects. Patient should consult prescriber for additional questions.
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- Drug class: loop diuretics
- Furosemide (AHFS Monograph)
- Furosemide (FDA)
- Furosemide Injection (FDA)
- Furosemide Oral Solution (FDA)
- Furosemide Tablets (FDA)
- Specimen Collection Kit (FDA)
Other brands: Lasix