What is Spironolactone used for?

Spironolactone is indicated for: Cardiomyopathy adjunct, CHF adjunct (with furosemide).

Which species have cited Spironolactone dosing data?

Spironolactone dosing in the ExoticRx formulary covers 2 species: Cat (Domestic), Dog (Domestic).

Is Spironolactone a controlled substance?

Spironolactone is not federally scheduled in the US. Controlled-drug status differs by country — verify your local rules.

Spironolactone

US brand names:Aldactone

Calculate dosage

Sourced from published veterinary references. Awaiting credentialed clinical reviewer — our editorial process.

Spironolactone is dosed at 1–2 mg/kg PO q12h in dogs, per Acierno MJ, Brown S, Coleman AE, et al. ACVIM consensus statement: guidelines for the identification, evaluation, and management of systemic hypertension in dogs and cats. J Vet Intern Med. 2018;32(6):1803-1822. doi:10.1111/jvim.15331 — Verified against Plumb's Veterinary Drug Handbook, 10th Ed, p.1204 (2026-08-01).. Verify against current literature before clinical use.

Drug Class

Cardiovascular

Routes

Indications

Cardiomyopathy adjunctCHF adjunct (with furosemide)

Mechanism of Action

Competitively blocks aldosterone at mineralocorticoid receptors in the distal nephron. Potassium-sparing diuretic with anti-fibrotic cardiac effects.

Side effects & warnings

Hyperkalemia risk, especially with ACE inhibitors. Monitor electrolytes. Anti-androgenic effects (gynecomastia). Used in CHF as adjunct to furosemide. Give with food.

Evidence levels across 2 dose rules

Moderate×1Weak×1

Each ExoticRx dose rule is graded by the strength of its primary evidence — see the editorial process.

Backed by 2 published sources

· Acierno MJ, Brown S, Coleman AE, et al. ACVIM consensus statement: guidelines for the identification, evaluation, and management of systemic hypertension in dogs and cats. J Vet Intern Med. 2018;32(6):1803-1822. doi:10.1111/jvim.15331 — Verified against Plumb's Veterinary Drug Handbook, 10th Ed, p.1204 (2026-08-01).
· Plumb's Veterinary Drug Handbook (held edition 10th, 2023), Spironolactone monograph, printed p.1177 (corpus p.1204), CATS section: "Adjunctive treatment of hypertension (extra-label): 1 - 2 mg/kg PO every 12 hours." Superscript 21 resolves to Acierno MJ, Brown S, Coleman AE, et al. ACVIM consensus statement: guidelines for the identification, evaluation, and management of systemic hypertension in dogs and cats. J Vet Intern Med. 2018;32(6):1803-1822.

Sample dosing (2 of 2 cited rules)

A dog/cat sample is shown here. Cited dosing for all 2 species — reptiles, birds, pocket pets, livestock, and equine — is free on the per-species pages above. Pro adds the weight-based calculator for every species.

Species	Route	Dose	Frequency	Evidence	Source
Dog (Domestic)	PO	1–2 mg/kg	q12h	Moderate	Acierno MJ, Brown S, Coleman AE, et al. ACVIM consensus statement: guidelines for the identification, evaluation, and management of systemic hypertension in dogs and cats. J Vet Intern Med. 2018;32(6):1803-1822. doi:10.1111/jvim.15331 — Verified against Plumb's Veterinary Drug Handbook, 10th Ed, p.1204 (2026-08-01).
Cat (Domestic)	PO	1–2 mg/kg	q12h	Weak	Plumb's Veterinary Drug Handbook (held edition 10th, 2023), Spironolactone monograph, printed p.1177 (corpus p.1204), CATS section: "Adjunctive treatment of hypertension (extra-label): 1 - 2 mg/kg PO every 12 hours." Superscript 21 resolves to Acierno MJ, Brown S, Coleman AE, et al. ACVIM consensus statement: guidelines for the identification, evaluation, and management of systemic hypertension in dogs and cats. J Vet Intern Med. 2018;32(6):1803-1822.

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