Bumetanide

What it is

Bumetanide is a loop diuretic: a drug that makes the kidney pass much more salt and water into the urine. It is given as a tablet, as an injection into a vein or muscle, and since 2026 in the United States as a nasal spray. It is a sulfonamide-type molecule, and the label records that people who reacted allergically to furosemide have been treated successfully with bumetanide, which suggests a lack of cross-sensitivity. It is roughly forty times more potent per mg than furosemide, a ratio the label itself uses when substituting one for the other.

What the research says

Its established job is to shift fluid off people who are overloaded with it - swelling from heart failure, from kidney disease including the nephrotic syndrome, and from liver disease. The trials behind that are old, small and mostly measure weight, oedema and urine output rather than survival or hospital admission; we found no outcome trial showing bumetanide reduces death. Comparisons with furosemide find broadly similar diuresis. Its best-known off-label use, for autism spectrum disorder, was tested in two large phase 3 trials that both failed and were stopped early.

Evidence grade: Limited evidence.

How it works

Drug class: Loop diuretic (sulfonamide-type inhibitor of sodium-chloride reabsorption in the loop of Henle)

Bumetanide blocks the reabsorption of sodium and chloride in the loop of Henle and in the proximal and distal tubules of the kidney. Because sodium and chloride stay in the tubule, water follows them out, and a large volume of urine is produced. The label notes the effect on the distal tubule does not depend on blocking carbonic anhydrase or aldosterone. This wording is the label's own and is dated: section 12.1 of the nasal-spray label places the main action in the proximal and distal tubules as well as the loop of Henle, text carried over from the original 1980s bumetanide labelling, while the same label elsewhere describes the product simply as a loop diuretic. It should be read as the label's mechanism statement rather than as the current pharmacological account. (Source 1)

Boxed warning

Bumetanide is a potent diuretic which, if given in excessive amounts, can lead to a profound diuresis with water and electrolyte depletion. Therefore, careful medical supervision is required, and dose and dosage schedule have to be adjusted to the individual patient’s needs (see DOSAGE AND ADMINISTRATION ).

(Source 2)

What it is used for

• Bumetanide reliably produces diuresis, and a propensity-matched hospital comparison found total urine output similar to intravenous furosemide. We found no randomised outcome trial showing bumetanide reduces death or hospital admission in heart failure; the evidence is about fluid removal, not survival. Evidence: limited. (Source 3)
• An open randomised comparison with furosemide in severe renal oedema found significant weight loss and oedema reduction with bumetanide, but the difference between the two drugs was not significant and the trial's design did not allow a conclusion about comparative efficacy. Evidence: limited. (Source 4)
• A three-centre open randomised comparison in ascites from chronic liver disease found weight loss and reduced abdominal girth in both arms, statistically significant only in the bumetanide arm, but the furosemide arm was too small for valid statistical analysis. Evidence: limited. (Source 5)
• Two international phase 3 randomised placebo-controlled trials, each of 211 patients, were both terminated early because there was no significant difference from placebo on the primary endpoint or on any secondary endpoint, and the sponsor discontinued development. Earlier smaller trials and meta-analyses had reported benefit, so this is a clean example of a positive small-trial signal that did not survive adequately powered testing. Evidence: not-supported. (Source 6)

Interactions

• Potassium supplements (label): Bumetanide makes the body lose potassium, and the label directs that serum potassium be measured periodically and that potassium supplements or potassium-sparing diuretics be added if needed. In people with cirrhosis and ascites the label says supplemental potassium may prevent hypokalaemia and metabolic alkalosis. This is a compensating interaction rather than a dangerous one, but it means potassium intake is not a free variable for someone on this drug. (Source 7)
• Magnesium (label): Diuretics increase how much magnesium leaves in the urine, which can drop blood magnesium. The nasal-spray label lists hypomagnesaemia among the metabolic abnormalities bumetanide may cause. (Source 7)
• Calcium (label): The label records that bumetanide may increase how much calcium is lost in the urine, with low blood calcium as the result. (Source 7)
• Licorice (glycyrrhizin-containing root, sweets and herbal teas) (case reports): Licorice independently drives potassium out of the body by mimicking a mineralocorticoid, and a published case describes a woman who needed dozens of cardioversions for ventricular tachycardia caused by hypokalaemia traced to licorice-containing herbal medicine, with no other drug involved. Bumetanide lowers potassium too, so the two effects point the same way. We found no study of licorice taken together with bumetanide, so this is a case-report-grounded concern about an additive effect, not a measured interaction. (Source 8)
• Lithium (label): Diuretics including bumetanide cut how fast the kidney clears lithium, which raises lithium levels and the risk of lithium poisoning. The label says lithium should generally not be given with diuretics. (Source 9)
• Non-steroidal anti-inflammatory drugs (indomethacin) (pharmacokinetic study): Indomethacin flattens the rise in urine volume and sodium excretion that bumetanide produces, and blocks its effect on plasma renin, so the diuretic works less well. The label says concurrent therapy is not recommended. (Source 10)
• Aminoglycoside antibiotics and other ototoxic drugs (label): Both bumetanide and aminoglycosides can damage hearing, and the label says injected bumetanide should be avoided in people also receiving aminoglycosides, especially when kidney function is impaired, except in life-threatening situations. (Source 11)
• Probenecid (pharmacokinetic study): Pre-treatment with probenecid reduces both the sodium loss and the renin rise that bumetanide produces, probably by blocking its secretion into the kidney tubule, so the diuretic effect is antagonised. (Source 12)
• Other blood-pressure-lowering drugs (label): Bumetanide can amplify the effect of other antihypertensive drugs, which the label says may mean their dose has to come down. Limit: This bullet is from the ENBUMYST nasal-spray label, which keeps text written for the older oral and injectable bumetanide products: the first bullet of the same section warns against 'parenterally administered bumetanide' together with aminoglycoside antibiotics, and the nasal spray has no parenteral route at all. Read the potentiation of other blood-pressure drugs as a bumetanide effect rather than as something specific to the spray. (Source 13)
• Alcohol (theoretical): We found no study of alcohol taken with bumetanide. What is documented is that short-term alcohol intake itself causes blood pressure to fall on standing because it blunts the blood-vessel constriction that normally defends against it, in a double-blind randomised placebo-controlled study of 14 healthy volunteers. Bumetanide reduces blood volume and the label records hypotension in 0.8% of treated patients, so the two effects plausibly add; that addition has not been measured. (Source 14)

Stopping it

• There is no dependence or withdrawal syndrome described for bumetanide, and we found no deprescribing or taper trial for it. The label's stopping instructions are about kidney and electrolyte safety: it says that in progressive renal disease a marked rise in urea or creatinine, or the development of oliguria, is an indication for stopping treatment. (Source 15)
• The nasal-spray label repeats the same stopping rule in plainer form for worsening kidney function. (Source 16)
• Rather than a taper, the tablet label describes planned interruption as the preferred long-term pattern: alternate days, or three to four days on with one to two days off. (Source 17)

What goes wrong

The common harms of bumetanide recorded in the label are cramps, dizziness and low blood pressure, and the laboratory abnormalities are far more common than the symptoms. (Source 18)

• Official position, Low certainty.
• Size: not stated in the label text (pooled clinical experience and postmarketing reports)
• Who: Patients treated with bumetanide.
• How long: not stated.
• Result: Clinical adverse reactions probably or possibly related: muscle cramps 1.1%, dizziness 1.1%, hypotension 0.8%, headache 0.6%, nausea 0.6%, encephalopathy in patients with pre-existing liver disease 0.6%; one or more in about 4.1% of patients. Laboratory abnormalities: hyperuricaemia 18.4% of patients tested, hypochloraemia 14.9%, hypokalaemia 14.7%, azotaemia 10.6%, hyponatraemia 9.2%, increased serum creatinine 7.4%, hyperglycaemia 6.6%. Impaired hearing 0.5%. Serious skin reactions including Stevens-Johnson syndrome and toxic epidermal necrolysis have been reported.
• Funding: regulatory label, not a funded study.

Limit of this finding: These are label figures with no placebo comparison group, so they cannot be read as drug-attributable excess. Electrolyte changes are also the intended pharmacology of the drug, which is why the label calls them manifestations of its pharmacologic action. One piece of the label's typography matters for a reader: the list prints 'CO content (4.3%)' with no subscript. In context - sitting beside bicarbonate and the other electrolytes, and matching the monitoring list elsewhere in the labels - this is the blood's total carbon dioxide content, not carbon monoxide. The quote is left exactly as the label prints it.

Laboratory abnormalities reported have included hyperuricemia (in 18.4% of patients tested), hypochloremia (14.9%), hypokalemia (14.7%), azotemia (10.6%), hyponatremia (9.2%), increased serum creatinine (7.4%), hyperglycemia (6.6%), and variations in phosphorus (4.5%), CO content (4.3%), bicarbonate (3.1%) and calcium (2.4%). Although manifestations of the pharmacologic action of bumetanide, these conditions may become more pronounced by intensive therapy.

Excessive diuresis from bumetanide can empty the circulation, and the label sets out the full chain of consequences. (Source 19)

• Official position, Low certainty.
• Size: not stated.
• Who: Patients treated with bumetanide, with elderly patients named as higher risk.
• How long: not stated.
• Result: No rates given. The label names profound water loss, electrolyte depletion, dehydration, reduction in blood volume and circulatory collapse with the possibility of vascular thrombosis and embolism, particularly in elderly patients. The newer nasal-spray label adds hypovolaemia, hypokalaemia, azotaemia, hyponatraemia, hypochloraemic alkalosis, hypomagnesaemia, hypocalcaemia, hyperglycaemia and hyperuricaemia.
• Funding: regulatory label, not a funded study.

Bumetanide may cause fluid, electrolyte, and metabolic abnormalities such as hypovolemia, hypokalemia, azotemia, hyponatremia, hypochloremic alkalosis, hypomagnesemia, hypocalcemia, hyperglycemia, or hyperuricemia, particularly in patients receiving higher doses, patients with inadequate oral electrolyte intake, and in elderly patients. Excessive diuresis may cause dehydration and blood volume reduction with circulatory collapse and possibly vascular thrombosis and embolism, particularly in elderly patients. Serum electrolytes, CO2, BUN, creatinine, glucose, and uric acid should be monitored frequently during bumetanide therapy.

In people with liver cirrhosis and ascites, a sudden swing in electrolytes caused by the drug can tip them into hepatic encephalopathy and coma. (Source 20)

• Official position, Low certainty.
• Size: not stated.
• Who: Patients with hepatic cirrhosis and ascites.
• How long: not stated.
• Result: No rate is given in this section; the label's adverse-reaction list puts encephalopathy in patients with pre-existing liver disease at 0.6%.
• Funding: regulatory label, not a funded study.

In patients with hepatic cirrhosis and ascites, sudden alterations of electrolyte balance may precipitate hepatic encephalopathy and coma. Treatment in such patients is best initiated in the hospital with small doses and careful monitoring of the patient’s clinical status and electrolyte balance. Supplemental potassium and/or spironolactone may prevent hypokalemia and metabolic alkalosis in these patients.

Hearing damage from bumetanide is documented in animals rather than in human trials, and reversible tinnitus and hearing loss have been reported with loop diuretics including bumetanide. (Source 21)

• Animal study, Very low certainty.
• Size: cats, dogs and guinea pigs (numbers not stated)
• Who: Animal ototoxicity testing, plus human postmarketing reports.
• How long: not stated.
• Result: In the animal tests bumetanide was 5 to 6 times more potent than furosemide for ototoxicity, but because its diuretic potency is about 40 to 60 times furosemide, the label says the blood levels needed to produce ototoxicity will rarely be achieved. Potentiation of aminoglycoside ototoxicity has not been tested for bumetanide. In humans, impaired hearing appears in the label's adverse-reaction list at 0.5%.
• Funding: regulatory label, not a funded study.

Limit of this finding: An animal finding is not a human finding. The rate of ototoxicity in people taking bumetanide is not established by this passage; the label argues from potency ratios rather than from human data, and says the aminoglycoside interaction has not been tested for this drug.

In cats, dogs and guinea pigs, bumetanide has been shown to produce ototoxicity. In these test animals bumetanide was 5 to 6 times more potent than furosemide and, since the diuretic potency of bumetanide is about 40 to 60 times furosemide, it is anticipated that blood levels necessary to produce ototoxicity will rarely be achieved. The potential exists, however, and must be considered a risk of intravenous therapy, especially at high doses, repeated frequently in the face of renal excretory function impairment. Potentiation of aminoglycoside ototoxicity has not been tested for bumetanide. Like other members of this class of diuretics, bumetanide probably shares this risk.

In the two phase 3 autism trials, the adverse events more common on bumetanide than placebo were the predictable consequences of a diuretic. (Source 6)

• Randomized trial, Moderate certainty.
• Size: 422 patients across the two trials (214 on bumetanide, 208 on placebo)
• Who: Children and adolescents aged 2-17 with autism spectrum disorder.
• How long: 6 months.
• Result: No rates are given in the abstract. Treatment-emergent adverse events more frequent with bumetanide than placebo in both studies were thirst, polyuria, hypokalaemia and dry mouth.
• Funding: sponsor-run registration trials.

Limit of this finding: The abstract names the events but gives no numerators or denominators, so the size of the excess over placebo cannot be read from it.

In both studies, treatment-emergent adverse events that occurred more frequently with bumetanide than placebo included thirst, polyuria, hypokalemia, and dry mouth.

What the evidence supports

Intravenous bumetanide and intravenous furosemide produced similar total urine output in propensity-matched patients admitted with acute decompensated heart failure. (Source 3)

• Cohort study, Low certainty.
• Size: 120 patients (60 in each group) after propensity matching.
• Who: Adults admitted with acute decompensated heart failure who received intravenous bumetanide or furosemide within 48 hours of admission.
• How long: 24 hours after initiation of the diuretic regimen.
• Result: Total 24-hour urine output was similar between groups. Urine output per furosemide-equivalent mg was greater with bumetanide: 52 +/- 46 mL/mg versus 33 +/- 25 mL/mg (P = 0.007).
• Funding: not stated in the abstract.

Limit of this finding: This is a retrospective, propensity-matched observational comparison of urine output, not a randomised trial and not an outcome trial. It says nothing about symptoms, admissions or survival.

The total urine output was similar between groups. The bumetanide group did demonstrate a greater urine output: furosemide-equivalent response (52 ± 46 mL/mg vs. 33 ± 25 mL/mg; P = 0.007). Based on our analysis, similar urine output may be achieved with either intravenous bumetanide or furosemide in acute decompensated heart failure; however, a higher dose of furosemide may be required than what has been previously established as an equivalent dose to bumetanide to achieve a similar diuretic effect.

In severe renal oedema, bumetanide produced significant weight loss and oedema reduction, but was not shown to differ from furosemide. (Source 4)

• Randomized trial, Very low certainty.
• Size: not stated in the abstract.
• Who: Patients with severe renal oedema, open parallel randomised comparison with furosemide.
• How long: Long-term; weight loss significant at most observation times during the first eight weeks and oedema reduction significant throughout the trial.
• Result: Weight loss and reduction of oedema and of mean arterial pressure occurred in both groups; in the bumetanide group oedema reduction was significant throughout (P less than 0.05) while reduction in the furosemide group was not statistically significant, yet the differences between the two drugs were not significant. No deterioration in audiometry occurred in any patient, including 12 who entered with abnormal air audiograms.
• Funding: not stated in the abstract.

Limit of this finding: An open-label trial from 1981 with no stated sample size in the abstract. The authors say the design did not warrant a definitive conclusion about comparative efficacy with furosemide, so 'significant in one arm and not the other' must not be read as bumetanide being better.

In the bumetanide-treated group, weight loss was statistically significant at most observation times during the first eight weeks, and reduction in edema was significant throughout the trial (P less than 0.05). Reduction in these parameters in the furosemide-treated patients was not statistically significant. However, the differences between the diuresis and other changes produced by the two drugs were not significant.

In ascites from chronic liver disease, weight loss and reduced abdominal girth occurred with both bumetanide and furosemide, reaching statistical significance only in the bumetanide group. (Source 5)

• Randomized trial, Very low certainty.
• Size: 59 patients: 43 on bumetanide, 16 on furosemide.
• Who: Patients presenting with ascites as a complication of chronic liver disease, at three medical facilities.
• How long: One to 28 weeks.
• Result: Weight loss and decrease in abdominal girth occurred in both groups but was statistically significant only in the bumetanide-treated patients. No hepatic encephalopathy developed. One furosemide patient was discontinued for severe electrolyte imbalance. Differences in electrolyte and uric acid changes were not statistically significant.
• Funding: not stated in the abstract.

Limit of this finding: The authors state plainly that the furosemide group was too small for valid statistical analysis, so the significance in one arm and not the other reflects group size, not a demonstrated advantage. This is an open-label 1981 study.

Weight loss and decrease in abdominal girth following diuretic action occurred in both groups but was statistically significant only in the bumetanide treated patients. Because of the small number of patients on furosemide, valid statistical analysis could not be obtained.

An older comparison of adverse reactions found bumetanide no worse than furosemide and possibly safer on audiometry. (Source 22)

• Expert review, not systematic, Very low certainty.
• Size: 493 patients on bumetanide compared with 220 on furosemide, drawn from 58 clinical studies.
• Who: Patients with oedema secondary to congestive heart failure and renal and hepatic disease.
• How long: not stated.
• Result: No rates are reported in the abstract. The authors conclude bumetanide, like furosemide, is an effective diuretic free of significant adverse effects within the recommended dose range, and that audiometric studies suggest bumetanide is possibly safer than furosemide for ototoxicity.
• Funding: not stated in the abstract.

Limit of this finding: This is a 1981 pooled summary of 58 studies with no stated systematic method, not a systematic review or a randomised comparison, and it reports no rates. The phrase 'free of significant adverse effects' sits badly beside the same drug's own label, which records hypokalaemia in 14.7% and hyperuricaemia in 18.4% of patients tested, so a reader should not conclude the drug is free of electrolyte harm.

The results indicate that bumetanide, as furosemide, is an effective diuretic free of significant adverse effects when administered in doses within the recommended therapeutic dose range. Audiometric studies suggest that bumetanide is possibly safer than furosemide with regard to ototoxicity.

What the evidence does not support

Two large phase 3 randomised placebo-controlled trials of bumetanide in autism spectrum disorder both failed and were stopped early. (Source 6)

• Randomized trial, High certainty.
• Size: 211 patients in each study (bumetanide n = 107, placebo n = 104), 422 in total.
• Who: Children and adolescents with autism spectrum disorder: aged 7-17 years in SIGN 1 (NCT03715166), aged 2-6 years in SIGN 2 (NCT03715153), international and multi-centre.
• How long: 6-month double-blind treatment period, primary endpoint at Week 26.
• Result: The primary endpoint, change in Childhood Autism Rating Scale 2 total raw score from baseline to Week 26, decreased in both the bumetanide and placebo groups with no statistically significant difference between groups. No differences on any secondary endpoint (Social Responsiveness Scale-2, Clinical Global Impression Scale, Vineland Adaptive Behavior Scale) in either study. Both studies were terminated early for absence of any significant difference.
• Funding: sponsor-run registration trials; the abstract records that the sponsor discontinued development of bumetanide for this condition.

Both studies were terminated early due to absence of any significant difference between bumetanide and placebo in the overall studied populations. In both studies, CARS2 total raw score decreased from baseline to Week 26 in the bumetanide and placebo groups, with no statistically significant difference between groups. No differences were observed between treatment groups for any of the secondary efficacy endpoints in either study.

Where the research disagrees

Whether bumetanide improves symptoms of autism spectrum disorder

• Fuentes and colleagues, 2023, reporting the two phase 3 trials (SIGN 1 and SIGN 2, 422 patients), rct: These large phase III trials failed to demonstrate a benefit of bumetanide for the treatment of pediatric ASD compared with placebo. Consequently, the sponsor has discontinued the development of bumetanide for the treatment of this condition. (Source 6)
• Wang and colleagues, 2021, meta-analysis of six earlier randomised trials (496 participants), meta-analysis: The results showed that bumetanide could significantly improve the severity of the ASD symptoms measured by CARS and SRS. There was also evidence that bumetanide had positive effect on the core symptoms of ASD such as the SA and RRB, but there was no statistically significant effect on sensory symptoms. (Source 23)
• Hendi and colleagues, 2026, updated meta-analysis, meta-analysis: Although statistically significant improvements were observed on some measures, we cannot conclude the superiority of bumetanide in alleviating ASD symptoms. Further large clinical trials should be conducted to determine the effect of bumetanide on different symptoms of ASD and the variation in treatment effect among different patient populations. (Source 24)

Whether bumetanide carries a boxed warning - the answer differs by product

• Bumetanide tablets (label effective 2026-06-03) and bumetanide injection (label effective 2026-07-08), both in the older non-PLR format, position: Bumetanide Injection, USP is a potent diuretic which, if given in excessive amounts, can lead to a profound diuresis with water and electrolyte depletion. Therefore, careful medical supervision is required, and dose and dosage schedule have to be adjusted to the individual patient (Source 25)
• ENBUMYST bumetanide nasal spray (label effective 2026-08-27), written in the newer Highlights format, which carries no coded boxed-warning section at all and puts the same material under Warnings and Precautions, position: Fluid, Electrolyte, and Metabolic Abnormalities: Monitor serum electrolytes, CO2, BUN, creatinine, glucose and uric acid. (5.1) Worsening Renal Function: Monitor for dehydration and azotemia. (5.2) Ototoxicity: Avoid higher than recommended doses. (5.3) (Source 26)

How much

• Reference intake: There is no reference intake for a prescription diuretic; dosing is set by the prescriber. As a position, the tablet label with an effective date of 2026-06-03 records a usual total daily dosage of 0.5 mg to 2 mg, in most patients given as a single dose. (Source 17)
• Upper limit: The tablet label's stated ceiling, as a position dated 2026-06-03, is a maximum daily dose of 10 mg, and it records that in patients with hepatic failure the dosage is kept to a minimum. The label also states a bumetanide-to-furosemide substitution ratio of about 1:40. (Source 17)
• Studied: The 1981 renal-oedema comparison used bumetanide 1 mg against furosemide 40 mg, with graded increases to daily maxima of 10 mg bumetanide and 400 mg furosemide. (Source 4)
• Studied: The two phase 3 autism trials gave children and adolescents bumetanide oral solution twice daily, or placebo twice daily, across a 6-month double-blind treatment period. (Source 6)

A common belief, and what the research shows

The belief: Bumetanide is a treatment for autism.

What the research shows: Two adequately powered phase 3 randomised placebo-controlled trials, one in children aged 7-17 and one in children aged 2-6, both stopped early because bumetanide did no better than placebo on the primary endpoint or on any secondary endpoint, and the sponsor ended development: Both studies were terminated early due to absence of any significant difference between bumetanide and placebo in the overall studied populations. The earlier positive signal came from smaller trials and meta-analyses of them, and even the 2026 updated meta-analysis stops short of a conclusion: we cannot conclude the superiority of bumetanide in alleviating ASD symptoms. Further large clinical trials should be conducted to determine the effect of bumetanide on different symptoms of ASD and the variation in treatment effect among different patient populations.

Questions and answers

What is it?

Bumetanide is a prescription loop diuretic - a water tablet. It comes as a tablet, an injection into a vein or muscle, and a nasal spray. It is a sulfonamide-type drug, and the tablet label notes that people who had allergic reactions to furosemide have been treated successfully with bumetanide, which suggests the two do not cross-react. (Source 27)

What does it do in the body?

It blocks the kidney from reabsorbing sodium and chloride in the loop of Henle and the proximal and distal tubules. Salt that stays in the tubule drags water with it, so a large volume of urine is produced and fluid comes off the body. The label notes this does not depend on blocking carbonic anhydrase or aldosterone. One caution: this is the label's own mechanism wording and it is dated - it places the main action in the proximal and distal tubules as well as the loop of Henle, text carried over from the original bumetanide labelling, while the same label elsewhere describes the product simply as a loop diuretic. (Source 1)

Is it good or bad for you?

It is useful in one setting and dangerous in another, which is exactly what its boxed warning says: it is a potent diuretic that in excess causes profound diuresis with water and electrolyte depletion. For people genuinely overloaded with fluid it removes that fluid reliably. For people who are not, or in too high a dose, it empties the circulation and strips potassium, sodium, magnesium and calcium. There is no outcome trial we found showing it extends life. The boxed warning quoted here is the bumetanide tablet label's. The injection label carries the same warning; the ENBUMYST nasal spray carries no boxed warning at all and puts the same fluid and electrolyte material under its Warnings and Precautions section instead, so the warning should not be attributed to the spray. (Source 2)

How do you get more of it?

There is no food, supplement or behaviour that provides bumetanide; it is prescription-only. As a position, the tablet label dated 2026-06-03 records a usual total daily dosage of 0.5 mg to 2 mg, given as a single dose in most patients, with a maximum daily dose of 10 mg. That is the label's statement, not advice to a reader; the dose is a prescriber's decision. (Source 17)

If it is harmful, what reduces it?

The drug itself leaves quickly: the label records a half-life of 1 to 1.5 hours after oral or injected doses, with 81% of a labelled dose recovered in urine. What takes longer to correct is what it has done to fluid and electrolytes, and the label's instruction when kidney function worsens is to stop the drug rather than to taper it. (Source 16)

Why might someone be low in it or missing it?

Nobody is naturally low in a manufactured diuretic. The reasons someone is not given it are the label's contraindications: no urine output at all, hepatic coma, severe electrolyte depletion until it is corrected, or hypersensitivity to the drug. Treatment is also stopped if urea or creatinine climb markedly or urine output falls in progressive kidney disease. (Source 15)

Which whole foods contain it or feed it?

No whole food contains bumetanide. Food matters in the opposite direction: because the drug strips potassium and magnesium, the label directs that potassium be measured periodically and supplements or potassium-sparing diuretics added if needed, and warns particularly about people on low-salt diets. Licorice is the food most clearly documented to push potassium down on its own. (Source 7)

What happens if you do not have it?

Not taking bumetanide is not a deficiency. If the fluid overload it treats is left untreated, the swelling of heart, kidney or liver disease persists - that is the condition the label approves it for. The approved indication is the treatment of oedema associated with congestive heart failure and with hepatic and renal disease including the nephrotic syndrome, and we found no trial showing the drug changes survival. (Source 27)

How can you test for it?

The relevant tests are blood tests on the person, not a test for the drug. The label directs monitoring of serum electrolytes, carbon dioxide, urea nitrogen, creatinine, glucose and uric acid, and the laboratory abnormality rates in the label show why: hyperuricaemia in 18.4% of patients tested, hypokalaemia in 14.7% and hyponatraemia in 9.2%. Blood levels of bumetanide itself are not measured in ordinary care. (Source 19)

References

1. DailyMed (U.S. National Library of Medicine), SPL setid d6f752c5-d2bd-4f77-9611-ca2110066d1f. ENBUMYST (bumetanide) nasal spray (Corstasis USA LLC) - DailyMed Structured Product Label, section: 12.1 Mechanism of Action. 2026. Read the source
2. DailyMed (U.S. National Library of Medicine), SPL setid 8914d8bf-61b7-4cd2-a8ef-7e1c5df37828. Bumetanide Tablets, USP (Sandoz Inc) - DailyMed Structured Product Label, section: Boxed Warning section. 2026. Read the source
3. Journal of cardiovascular pharmacology. Comparison of Urine Output Response of Intravenous Bumetanide and Furosemide in Acute Decompensated Heart Failure: An Observational Analysis.. 2025. PMID 39636041, DOI 10.1097/FJC.0000000000001658. Read the source
4. Journal of clinical pharmacology. Long-term bumetanide treatment of renal edema. Comparison with furosemide.. 1981. PMID 7040493, DOI 10.1002/j.1552-4604.1981.tb05669.x. Read the source
5. Journal of clinical pharmacology. A comparison of bumetanide and furosemide in the treatment of ascites. Cooperative study.. 1981. PMID 7338582, DOI 10.1002/j.1552-4604.1981.tb05687.x. Read the source
6. Autism research : official journal of the International Society for Autism Research. Bumetanide oral solution for the treatment of children and adolescents with autism spectrum disorder: Results from two randomized phase III studies.. 2023. PMID 37794745, DOI 10.1002/aur.3005. Read the source
7. DailyMed (U.S. National Library of Medicine), SPL setid 8914d8bf-61b7-4cd2-a8ef-7e1c5df37828. Bumetanide Tablets, USP (Sandoz Inc) - DailyMed Structured Product Label, section: General. 2026. Read the source
8. Translational and clinical pharmacology. Electrical storm induced by hypokalemia associated with herbal medicines containing licorice.. 2019. PMID 32055584, DOI 10.12793/tcp.2019.27.2.69. Read the source
9. DailyMed (U.S. National Library of Medicine), SPL setid 8914d8bf-61b7-4cd2-a8ef-7e1c5df37828. Bumetanide Tablets, USP (Sandoz Inc) - DailyMed Structured Product Label, section: Lithium. 2026. Read the source
10. DailyMed (U.S. National Library of Medicine), SPL setid 8914d8bf-61b7-4cd2-a8ef-7e1c5df37828. Bumetanide Tablets, USP (Sandoz Inc) - DailyMed Structured Product Label, section: Indomethacin. 2026. Read the source
11. DailyMed (U.S. National Library of Medicine), SPL setid 8914d8bf-61b7-4cd2-a8ef-7e1c5df37828. Bumetanide Tablets, USP (Sandoz Inc) - DailyMed Structured Product Label, section: Drugs with Ototoxic Potential (see WARNINGS). 2026. Read the source
12. DailyMed (U.S. National Library of Medicine), SPL setid d6f752c5-d2bd-4f77-9611-ca2110066d1f. ENBUMYST (bumetanide) nasal spray (Corstasis USA LLC) - DailyMed Structured Product Label, section: 7.1 Effects of Other Drugs on Bumetanide. 2026. Read the source
13. DailyMed (U.S. National Library of Medicine), SPL setid d6f752c5-d2bd-4f77-9611-ca2110066d1f. ENBUMYST (bumetanide) nasal spray (Corstasis USA LLC) - DailyMed Structured Product Label, section: 7.2 Effects of Bumetanide on Other Drugs. 2026. Read the source
14. Circulation. Alcohol potentiates orthostatic hypotension : implications for alcohol-related syncope.. 2000. PMID 10653831, DOI 10.1161/01.cir.101.4.398. Read the source
15. DailyMed (U.S. National Library of Medicine), SPL setid 8914d8bf-61b7-4cd2-a8ef-7e1c5df37828. Bumetanide Tablets, USP (Sandoz Inc) - DailyMed Structured Product Label, section: CONTRAINDICATIONS. 2026. Read the source
16. DailyMed (U.S. National Library of Medicine), SPL setid d6f752c5-d2bd-4f77-9611-ca2110066d1f. ENBUMYST (bumetanide) nasal spray (Corstasis USA LLC) - DailyMed Structured Product Label, section: 5.2 Worsening Renal Function. 2026. Read the source
17. DailyMed (U.S. National Library of Medicine), SPL setid 8914d8bf-61b7-4cd2-a8ef-7e1c5df37828. Bumetanide Tablets, USP (Sandoz Inc) - DailyMed Structured Product Label, section: Oral Administration. 2026. Read the source
18. DailyMed (U.S. National Library of Medicine), SPL setid 8914d8bf-61b7-4cd2-a8ef-7e1c5df37828. Bumetanide Tablets, USP (Sandoz Inc) - DailyMed Structured Product Label, section: ADVERSE REACTIONS. 2026. Read the source
19. DailyMed (U.S. National Library of Medicine), SPL setid d6f752c5-d2bd-4f77-9611-ca2110066d1f. ENBUMYST (bumetanide) nasal spray (Corstasis USA LLC) - DailyMed Structured Product Label, section: 5.1 Fluid, Electrolyte, and Metabolic Abnormalities. 2026. Read the source
20. DailyMed (U.S. National Library of Medicine), SPL setid 8914d8bf-61b7-4cd2-a8ef-7e1c5df37828. Bumetanide Tablets, USP (Sandoz Inc) - DailyMed Structured Product Label, section: Hypokalemia. 2026. Read the source
21. DailyMed (U.S. National Library of Medicine), SPL setid 8914d8bf-61b7-4cd2-a8ef-7e1c5df37828. Bumetanide Tablets, USP (Sandoz Inc) - DailyMed Structured Product Label, section: Ototoxicity. 2026. Read the source
22. Journal of clinical pharmacology. Comparison of adverse reactions to bumetanide and furosemide.. 1981. PMID 7338572, DOI 10.1002/j.1552-4604.1981.tb05673.x. Read the source
23. Frontiers in psychiatry. Treatment Effect of Bumetanide in Children With Autism Spectrum Disorder: A Systematic Review and Meta-Analysis.. 2021. PMID 34867539, DOI 10.3389/fpsyt.2021.751575. Read the source
24. European child & adolescent psychiatry. The Efficacy and Safety of Bumetanide in Children with Autism Spectrum Disorder: An Updated Meta-analysis.. 2026. PMID 41165800, DOI 10.1007/s00787-025-02890-8. Read the source
25. DailyMed (U.S. National Library of Medicine), SPL setid 681b5e9d-e2c7-4f29-aaad-e06d4a528c11. Bumetanide Injection, USP (Hikma Pharmaceuticals USA Inc.) - DailyMed Structured Product Label, section: WARNING. 2026. Read the source
26. DailyMed (U.S. National Library of Medicine), SPL setid d6f752c5-d2bd-4f77-9611-ca2110066d1f. ENBUMYST (bumetanide) nasal spray (Corstasis USA LLC) - DailyMed Structured Product Label, section: 5 WARNINGS AND PRECAUTIONS (Highlights excerpt). 2026. Read the source
27. DailyMed (U.S. National Library of Medicine), SPL setid 8914d8bf-61b7-4cd2-a8ef-7e1c5df37828. Bumetanide Tablets, USP (Sandoz Inc) - DailyMed Structured Product Label, section: INDICATIONS AND USAGE. 2026. Read the source