Furosemide
Also called dihydroflumethiazide and methforylthiazidine.
A loop diuretic sold as Lasix, used for the fluid build-up of heart failure and for high blood pressure.
Sources and notes
- The introductionfrom sourceMoleculeFinder curated
- Other namesfrom sourceWikidataIts English label and aliases on Wikidata.
- Formula and weightcomputedPubChem
- 2D drawingcomputedPubChem structure, drawn by RDKit
- 3D modelfrom sourcePubChem 3D conformerLoaded after the page has painted, and on a phone only when you ask for it; the 2D drawing shows until it arrives.
Where you encounter it
Dispensed on prescription, not sold on a shelf. Furosemide on the product labels we hold.
Medicines
Every product and list we hold
Sources and notes
- The product labels and their strengthsfrom sourceDailyMed (FDA label)Each label lists the molecule as an ingredient, and an active ingredient at the strength shown.
- How it gets therefrom sourceMoleculeFinder curatedEach mark is set by hand on our lists, never inferred; a label's ingredient is added by the maker. A row with no mark data says Not marked.
- The line abovefrom sourceMoleculeFinder curatedFrom the group the molecule belongs to.
Explore its structure
Choose a part to light it up.
A carbon carrying both a C=O and an O-H, written COOH. In water it gives up that hydrogen, which is what makes the molecule an acid.
From: standard chemistry.
A sulfur carrying two oxygens and a nitrogen, written SO2N. It is a polar, sturdy group, the one the sulfa drugs are named for.
From: standard chemistry.
Fluorine, chlorine, bromine or iodine bonded to carbon. Each pulls electrons toward itself, and each is larger than the hydrogen the carbon would otherwise carry.
From: standard chemistry.
Sources and notes
- The drawingcomputedPubChem structure, drawn by RDKitThe page's one shipped drawing, with the chosen part lit in amber under it.
- The partscomputedFound by ruleEach part is found by a chemical pattern, never picked by hand atom by atom; its words say where they come from.
Compare a related molecule
Hydrochlorothiazide
Furosemide
Furosemide is a strong loop diuretic acting in the loop of Henle, while hydrochlorothiazide acts further along the kidney tubule and is gentler.
Hydrochlorothiazide vs Furosemide, side by sideSources and notes
- The sentencefrom sourceMoleculeFinder comparison notesThe pair's answer line.
- The two drawingscomputedPubChem structures, drawn by RDKitThe two drawings side by side.
Properties and sources
Calculated by PubChem
- Molecular formula
- C12H11ClN2O5S
- Molecular weight
- 330.74 g/mol
- XLogP3octanol/water, log units
- 2
- Polar surface areatopological
- 131 Ų
- H-bond donors
- 3
- H-bond acceptors
- 7
- Rotatable bonds
- 5
- Complexity
- 481
Measured LD50, HSDB via PubChem
800 mg/kg pure furosemide, rat, intravenous
An LD50 is an animal study measurement, not a dose for a person.
Reported Hazard label (GHS), ECHA, HSDB via PubChem
Danger Irritant pictogram (GHS07) and Health hazard pictogram (GHS08); hazard statements H315, H319, H335, H351, H360, H361
Reported Licence
The US Food and Drug Administration licenses Furosemide for human use (NDA 018267, authorized May 19, 1981). Drugs@FDA
Groups it belongs to
- Category
- Prescription medicine
- Family
- Blood-pressure medicines
- Chemical groups
- Carboxylic Acids, Amines, Aromatics, Halogenated
- Hazard classes
- Irritant, Health hazard, GHS Danger
C1=COC(=C1)CNC2=CC(=C(C=C2C(=O)O)S(=O)(=O)N)ClPubChem CID 3440 · Wikidata Q388801 · InChIKey ZZUFCTLCJUWOSV-UHFFFAOYSA-N · Data refreshed
Questions
- What is Furosemide?
- A loop diuretic sold as Lasix, used for the fluid build-up of heart failure and for high blood pressure.
- How toxic is Furosemide?
- The reported LD50 of Furosemide is 800 mg/kg (rat, iv). An LD50 is an animal study measurement, not a dose for a person. Its GHS hazard label carries the signal word Danger and the hazard pictograms Irritant and Health hazard. from sourcefrom source
- What kind of molecule is Furosemide?
- Furosemide has the formula C12H11ClN2O5S and a molecular weight of 330.74 g/mol. MoleculeFinder files it under blood-pressure medicines, in the prescription medicine group. from sourcefrom sourcefrom sourcefrom source
- What else is Furosemide called?
- Furosemide is also called dihydroflumethiazide and methforylthiazidine. from source
- Who licenses Furosemide as a medicine?
- The US Food and Drug Administration licenses Furosemide for human use (NDA 018267, authorized May 19, 1981). from source
Sources and notes
- Calculated valuescomputedPubChemComputed from the structure, so no laboratory conditions apply; complexity is PubChem's own structural score.
- LD50from sourceHSDB via PubChemOther values the sources report: rat, another route, 800 mg/kg. The page shows the one LD50 the site uses everywhere.
- Hazard labelfrom sourceECHA, HSDB via PubChemThe label combines these classifications.
- ECHAfrom sourceAttributionSource: European Chemicals Agency, echa.europa.eu.
- Licencefrom sourceDrugs@FDARead 2026-10-21.
- Data refreshedfrom sourceMoleculeFinder2026-11-09
Keep exploring
Sources and notes
- Compared side by sidefrom sourceMoleculeFinder comparison notesA molecule we compare it with on its own page.
- The drawingscomputedPubChem structures, drawn by RDKit