Pet Drug Reports

Ingredients

Active ingredient · pooled across combinations

Spironolactone: adverse event reports, pooled

5 ingredient sets in reports · 1 FDA-approved application in the Green Book

297reports naming the ingredient, 2011–20260% of all reports · about 21 a year
65reports, 12 months to March 202651 in the 12 months before
51.9%classed serious, as reportedall reports: 38.6%
83.5%of reports concern dogscat 7.4%

Spironolactone appears, alone or combined with other ingredients, in 297 reports in FDA's animal adverse event database (November 2011 to March 2026). The figures here pool all 5 ingredient sets that include it.

The Green Book lists 1 FDA-approved application containing it. openFDA masks brand and manufacturer names in adverse event records, so the reports counted here cannot be attributed to a particular brand.

65 reports arrived in the 12 months to March 2026, up 27% from 51 in the 12 months before. FDA posts reports quarterly with a delay of three to six months, so the newest months are incomplete and usually grow in later releases. That is about 21 reports a year over its reporting history and 0% of all reports.

Pooled across every set, the terms listed most often are vomiting (21.5%), lethargy (18.2%) and diarrhoea (12.5%). Many drugs combine several ingredients, and many reports list several drugs, so a term on this page may relate to any of them or to none.

Of reports that state seriousness, 51.9% were classed as serious (38.6% across the whole database); 18.5% record a death or euthanasia (6.4% overall). Ingredients used in older or sicker animals, or in anaesthesia and cancer care, carry higher shares for that reason alone.

Ingredient sets that include spironolactone

Active ingredients recorded for the drugReportsShare of this page's reportsLatest 12 months
Spironolactone20067.3%48
Benazepril hydrochloride + Spironolactone7525.3%11
Benazepril + Spironolactone144.7%5
Hydrochlorothiazide + Spironolactone62%0
Pimobendan + Spironolactone20.7%1

Ordered by report count. FDA states that these data "cannot be used to estimate the risk associated with the product or compare one drug or device product with another"; counts follow sales volume and years on the market. A report can list more than one set, so shares can add to more than 100%.

Signs listed in reports, pooled

share of spironolactone reports listing the termall reports in the database

  1. Vomiting21.5%64
  2. Lethargy[unusually tired or inactive]18.2%54
  3. Diarrhoea[diarrhea]12.5%37
  4. Elevated blood urea nitrogen (BUN)[a kidney value above the normal range]11.4%34
  5. Death by euthanasia[the animal was euthanized]11.1%33
  6. Anorexia[not eating]9.1%27
  7. Lack of efficacy - NOS[the product did not have the expected effect]9.1%27
  8. Death8.4%25
  9. Elevated creatinine[a kidney value above the normal range]8.1%24
  10. Elevated alanine aminotransferase (ALT)[a liver enzyme above the normal range]6.1%18
  11. Seizure NOS[seizure, type not specified]5.4%16
  12. Ataxia[unsteady, uncoordinated movement]5.1%15
  13. Hyperphosphataemia[high blood phosphate]4.4%13
  14. Cough4%12
  15. Elevated serum alkaline phosphatase (SAP)[a liver and bone enzyme above the normal range]4%12
  16. Behavioural disorder NOS[behaviour change, type not specified]3.7%11
  17. Emesis[vomiting]3.7%11
  18. Hypokalaemia[low blood potassium]3.4%10
  19. Other abnormal test result NOS[abnormal laboratory result, type not specified]3.4%10
  20. Panting3.4%10
  21. Hyperglycaemia[high blood sugar]3%9
  22. Polyuria[passing more urine than usual]3%9
  23. Tablets, Abnormal[a product quality report, not a sign in an animal]3%9
  24. Ascites[fluid in the abdomen]2.7%8

Pooled across every ingredient set and every report that names the ingredient. One report can list several terms and several drugs; a term here may relate to any of them or to none.

Monthly reports by species, five years

Dog178 · peak 14
Apr 2021: 3May 2021: 1Jun 2021: 1Jul 2021: 7Aug 2021: 3Sep 2021: 2Oct 2021: 2Nov 2021: 1Jan 2022: 1Feb 2022: 1Mar 2022: 1Apr 2022: 1May 2022: 6Jun 2022: 5Jul 2022: 3Aug 2022: 2Oct 2022: 1Nov 2022: 3Jan 2023: 1Mar 2023: 1Apr 2023: 2Jun 2023: 14Jul 2023: 1Aug 2023: 1Sep 2023: 2Nov 2023: 4Dec 2023: 6Jan 2024: 7Feb 2024: 3Mar 2024: 1Apr 2024: 2May 2024: 5Jun 2024: 8Jul 2024: 3Aug 2024: 6Sep 2024: 3Oct 2024: 1Nov 2024: 1Dec 2024: 2Jan 2025: 5Feb 2025: 2Mar 2025: 2Apr 2025: 1May 2025: 3Jun 2025: 4Jul 2025: 7Aug 2025: 2Sep 2025: 1Oct 2025: 5Nov 2025: 6Dec 2025: 8Jan 2026: 7Feb 2026: 4Mar 2026: 32022202320242025
Cat17 · peak 3
Mar 2022: 1Jan 2023: 1Aug 2023: 1Nov 2023: 1Jul 2024: 1Aug 2024: 1Oct 2024: 1Dec 2024: 1Jan 2025: 1Apr 2025: 3Oct 2025: 2Dec 2025: 32022202320242025
Horse0 · peak 1
2022202320242025
Other26 · peak 2
Jun 2021: 1Nov 2021: 1Dec 2021: 1May 2022: 1Sep 2022: 1Nov 2022: 2Dec 2022: 1Apr 2023: 2Jun 2023: 2Nov 2023: 1Jan 2024: 1Aug 2024: 1Oct 2024: 1Dec 2024: 1Jan 2025: 1Feb 2025: 1Mar 2025: 1Jun 2025: 1Aug 2025: 2Oct 2025: 1Nov 2025: 22022202320242025

By month of receipt; each panel has its own scale. The newest months are incomplete because FDA posts reports with a delay of three to six months.

032642011: 220112012: 720122013: 1320132014: 1220142015: 420152016: 1120162017: 620172018: 820182019: 620192020: 420202021: 2620212022: 3020222023: 4020232024: 5020242025: 6420252026: 142026

Outcomes, report types and ages

Outcome recorded in the report

Recovered/Normal21.5%64
Recovered with Sequela1.3%4
Ongoing29.3%87
Died8.4%25
Euthanized10.8%32
Outcome Unknown22.6%67

What kind of report it was

Safety issue81.5%242
Lack of expected effectiveness3.4%10
Both safety and lack of expected effectiveness6.4%19
Manufacturing or product defect8.4%25
Other0.3%1

Species

Dog83.5%248
Cat7.4%22
Human exposure1.3%4

Age of the animal

Under 1 year0.7%2
1 to 3 years5.4%16
4 to 7 years4.7%14
8 to 11 years24.2%72
12 years and over55.2%164
Age not given9.8%29

Coloured bar: reports naming spironolactone. Grey bar: all 1,357,245 reports. Outcomes are as stated by the reporter; FDA has not necessarily determined whether any product played a part.

In context

MeasureSpironolactoneAll reports
Reports2971,357,245
Latest 12 months against the 12 before+27%-5%
Classed serious, of reports stating it51.9%38.6%
Death or euthanasia recorded, per 1,000 reports185.263.8
Filed as lack of expected effectiveness (wholly or partly)9.8%23%

Shares of reports, not of animals treated: how many animals receive the ingredient is not public. Ingredients used in anaesthesia, cancer care or in old animals carry more serious outcomes in their reports for that reason alone.

FDA-approved products containing spironolactone (Green Book)

Reference information, not report statistics. openFDA masks brand and manufacturer names in adverse event records, so the reports counted here cannot be attributed to a particular brand. The list below is the FDA Green Book as of 30 Sep 2026; nothing on this page says which of these products, if any, a report concerned.

Trade nameActive ingredientsSponsorApproved forApplication
CardalisBenazepril hydrochloride, SpironolactoneCeva Sante AnimaleDogsNADA 141-538

Species are the major species the Green Book search lists for the application ("—" where it lists another species or none). Approval dates are not part of the Green Book listing files and are not shown. Pioneer applications (NADA) come first, then generics (ANADA).

Questions about spironolactone reports

How many FDA adverse event reports mention spironolactone?

297 reports through March 2026, 65 of them in the latest 12 months, counting spironolactone alone and in combinations.

Which brands do these reports concern?

That cannot be known from the public data. openFDA masks brand and manufacturer names in adverse event records, so the reports counted here cannot be attributed to a particular brand. The Green Book reference list on this page names approved products containing spironolactone without any counts.

In which combinations is spironolactone reported?

Spironolactone (67.3% of these reports), Benazepril hydrochloride + Spironolactone (25.3% of these reports), Benazepril + Spironolactone (4.7% of these reports), Hydrochlorothiazide + Spironolactone (2% of these reports) and Pimobendan + Spironolactone (0.7% of these reports).

What reactions are reported for spironolactone?

vomiting (21.5%), lethargy (18.2%), diarrhoea (12.5%), elevated blood urea nitrogen (BUN) (11.4%) and death by euthanasia (11.1%). Shares are of reports naming the ingredient; one report can list several terms.

Which animals are these reports about?

dog (83.5%), cat (7.4%) and human exposure (1.3%).

Does a high count mean spironolactone is a problem ingredient?

A count cannot show that. FDA states that "there is no certainty that the reported drug or device caused the adverse event" and that the event "may have been related to an underlying disease, other drugs used at the same time or other non-drug related sources." Widely used ingredients collect more reports because more animals receive them.

How do I report a problem?

Call the drug company using the number on the label, or send Form FDA 1932a to FDA. See the guide on how to report.

Where this comes from. Counts are built from the openFDA Animal & Veterinary adverse event bulk files released 28 Sep 2026, which hold reports FDA's Center for Veterinary Medicine received through 31 Mar 2026. openFDA masks brand and manufacturer names in these files, so drugs are counted by the active ingredients each record discloses and no figure is attributed to a brand, application or company. Ingredient names, and the separate reference lists of approved products, follow the FDA Green Book as of 30 Sep 2026. Ingredient names follow the Green Book; salts and forms are kept as FDA lists them. Drug entries are matched by the active ingredients their unmasked ingredient field discloses. No report text, lot numbers or reporter details are published. See the methodology and sources; FDA's record is authoritative, and corrections are handled within five working days.