Two medicines, side by side
Spironolactone vs furosemide
Spironolactone and furosemide are both labeled for high blood pressure, heart failure and edema (fluid retention). Drugs@FDA records approvals of spironolactone since 1960 and of furosemide since 1966. Pharmacies paid $0.0426 per spironolactone 25 mg tablet and $0.490 per mL (Furosemide 20 mg/2 mL vial) (NADAC, October 7, 2026); the strengths differ, so the two prices are not like for like. In FDA's classes, spironolactone is an aldosterone antagonist and furosemide a loop diuretic.
Check it at the source: the spironolactone FDA label on DailyMed (effective November 28, 2025); the furosemide FDA label on DailyMed (effective September 30, 2025).
Highlights of the spironolactone record
Spironolactone (Aldactone) · label of November 28, 2025
Used for
From the label: indicationsALDACTONE is an aldosterone antagonist indicated for: • The treatment of NYHA Class III–IV heart failure and reduced ejection fraction to increase survival, manage edema, and to reduce the need for hospitalization for heart failure ( 1.1 ). • Use as an add-on therapy for the treatment of hypertension, to lower blood pressure. […]
On the market
- Earliest approval on file
- January 21, 1960
- Generic labelers
- 38 labelers
- Pharmacy cost
- $0.0426 per tablet
Supply and safety
- Shortage
- A presentation being discontinued
- Recalls
- 6
Highlights of the furosemide record
Furosemide (Lasix) · label of September 30, 2025
Used for
From the label: indicationsEdema LASIX is indicated in adults and pediatric patients for the treatment of edema associated with congestive heart failure, cirrhosis of the liver, and renal disease, including the nephrotic syndrome. LASIX is particularly useful when an agent with greater diuretic potential is desired. […]
On the market
- Earliest approval on file
- July 1, 1966
- Generic labelers
- 52 labelers
- Pharmacy cost
- $0.490 per mL
Supply and safety
- Shortage
- In shortage
- Recalls
- 8
Source: FDA drug labels via openFDA (Spironolactone label of November 28, 2025, Furosemide label of September 30, 2025); NDC Directory, Drugs@FDA, NADAC, FDA shortages and recalls (October 8, 2026)
How do spironolactone and furosemide differ on the record?
In FDA's classes, spironolactone is an aldosterone antagonist and furosemide a loop diuretic.
Half-life, in each label's words: Spironolactone, “The mean half-life values of its metabolites including canrenone, 7-α-(thiomethyl) spirolactone (TMS), and …”; Furosemide, “The terminal half-life of furosemide is approximately 2 hours.”
Generics: spironolactone since 1980; furosemide since 1985 (Drugs@FDA).
| Spironolactone | Furosemide | |
|---|---|---|
| Labeled for | Heart failure, Edema (fluid retention), High blood pressure | Heart failure, High blood pressure, Edema (fluid retention) |
| Pharmacologic class | Aldosterone Antagonist | Loop Diuretic |
| How it works (label) | Spironolactone and its active metabolites are specific pharmacologic antagonists of aldosterone, acting primarily through competitive binding of receptors at the aldosterone-dependent sodium-potassium exchange site in the distal convoluted … | n/a |
| Half-life (label) | The mean half-life values of its metabolites including canrenone, 7-α-(thiomethyl) spirolactone (TMS), and 6-β-hydroxy-7-α-(thiomethyl) spirolactone (HTMS) are 16.5, 13.8, and 15 hours, respectively. | The terminal half-life of furosemide is approximately 2 hours. |
| Earliest approval on file (Drugs@FDA) | January 21, 1960 | July 1, 1966 |
| First generic approved | May 7, 1980 | September 26, 1985 |
| Generic labelers (NDC) | 38 labelers | 52 labelers |
| Pharmacy cost (NADAC, each one's most listed form; strengths differ) | $0.0426 per tablet (Spironolactone 25 mg tablet) | $0.490 per mL (Furosemide 20 mg/2 mL vial) |
| 12-month price change | -14% | +31% |
| Boxed warning | No | No |
| Shortage now | A presentation being discontinued | In shortage |
| Recalls recorded | 6 | 8 |
| FAERS reports (a report is not proof of cause; counts follow how widely a medicine is used) | 139,757 | 398,354 |
| DEA schedule | none | none |
Source: Drugs@FDA, FDA NDC Directory, CMS NADAC of October 7, 2026, FDA shortages and recalls, FAERS via openFDA (FDA files October 8, 2026)
What next?
- Alternatives to spironolactone
- every medicine labeled for the same conditions