Home/Medicines/Hydrochlorothiazide
All medicines

Hydrochlorothiazide

Prescription
Thiazide diuretic
Last reviewed 19 Apr 2026 · PetCare.AI Editorial Team
Species
Dog, Cat
Brands
3 available
Interactions
1 documented
Formulations
2

Mechanism of action

Inhibits sodium and chloride reabsorption in the distal convoluted tubule, promoting diuresis and reducing blood pressure

At a glance

Class
Thiazide diuretic
Schedule
Prescription
Storage
Store below 25°C, protect from light

Dosing

🐕

Dog

Edema / Hypertension / Adjunct for refractory CHF
Dose
2–4 mg/kg
Route
PO
Frequency
BID
Max dose
200 mg/dose; 400 mg/day
Duration: As needed; long-term for hypertension
🐈

Cat

Edema / Calcium oxalate urolithiasis prevention
Dose
1–2 mg/kg
Route
PO
Frequency
BID
Max dose
12.5 mg/dose; 25 mg/day
Duration: Long-term for urolithiasis prevention

Formulations

💊

Tablet — 2

Strength
12.5mg
Available in India
Strength
25mg
Available in India

Storage

Store below 25°C, protect from light

Safety

Absolute contraindications — do not use

  • Anuria

Use with caution

  • Electrolyte imbalances
    May worsen hypokalemia

Adverse effects

Common
Polyuria
Polydipsia
Hypokalemia
Serious
Severe dehydration
Hyponatremia
Hyperglycemia

Monitoring parameters

Serum electrolytesBUN/CreatinineBlood glucose

Interactions

Major — 1

Digoxin
major
Thiazide-induced hypokalemia increases sensitivity to digoxin toxicity
Management: Monitor potassium closely. Supplement potassium if needed. Watch for digoxin toxicity signs.

Brands

International

HydroDiuril
MSD

India

Aquazide
Sun Pharma
Hydrazide
Cadila

FAQs

Frequently asked questions

›What is Hydrochlorothiazide?
Hydrochlorothiazide is a thiazide diuretic used in pets. Inhibits sodium and chloride reabsorption in the distal convoluted tubule, promoting diuresis and reducing blood pressure
›What is Hydrochlorothiazide used for in pets?
Hydrochlorothiazide is used in veterinary medicine for: Edema / Hypertension / Adjunct for refractory CHF; Edema / Calcium oxalate urolithiasis prevention.
›What is the Hydrochlorothiazide dose for dogs?
For dogs, Hydrochlorothiazide is typically dosed as follows — Edema / Hypertension / Adjunct for refractory CHF: 2–4 mg/kg PO BID. Always consult your veterinarian for a dose tailored to your pet's weight, age, and condition.
›What is the Hydrochlorothiazide dose for cats?
For cats, Hydrochlorothiazide is typically dosed as follows — Edema / Calcium oxalate urolithiasis prevention: 1–2 mg/kg PO BID. Always consult your veterinarian for a dose tailored to your pet's weight, age, and condition.
›What are the side effects of Hydrochlorothiazide?
Common: Polyuria, Polydipsia, Hypokalemia. Serious (call your vet immediately): Severe dehydration, Hyponatremia, Hyperglycemia.
›Does Hydrochlorothiazide need a prescription?
Yes. Hydrochlorothiazide is a prescription medication and should only be administered under veterinary supervision.
›When should Hydrochlorothiazide not be used?
Do not use Hydrochlorothiazide if: Anuria.

References

References

Textbooks & handbooks

  • Plumb, D.C. Plumb's Veterinary Drug Handbook. 10th ed., Wiley-Blackwell, 2023.
  • Vail, D.M., Thamm, D.H., & Liptak, J.M. (eds.). Withrow & MacEwen's Small Animal Clinical Oncology. 6th ed., Saunders/Elsevier, 2020.
  • Riviere, J.E., & Papich, M.G. (eds.). Veterinary Pharmacology and Therapeutics. 10th ed., Wiley-Blackwell, 2018.
  • National Research Council. Nutrient Requirements of Dogs and Cats. National Academies Press, Washington DC, 2006.
  • The Merck Veterinary Manual. Merck & Co., Online edition. https://www.merckvetmanual.com/

Clinical guidelines & consensus

  • Fletcher, D.J., Boller, M., Brainard, B.M., et al. "RECOVER Evidence and Knowledge Gap Analysis on Veterinary CPR." Journal of Veterinary Emergency and Critical Care, 2012;22(S1):S102–S131.
  • American Animal Hospital Association. 2018 AAHA Diabetes Management Guidelines for Dogs and Cats. AAHA Press.

Journals & peer-reviewed studies

  • Hogan, D.F., Fox, P.R., Jacob, K., et al. "Secondary prevention of cardiogenic arterial thromboembolism in the cat: The FAT CAT study." Journal of Veterinary Cardiology, 2015;17(Suppl 1):S306–S317.
  • Boswood, A., Häggström, J., Gordon, S.G., et al. "Effect of Pimobendan in Dogs with Preclinical Myxomatous Mitral Valve Disease and Cardiomegaly: The EPIC Study — A Randomized Clinical Trial." Journal of Veterinary Internal Medicine, 2016;30(6):1765–1779.
  • ASPCA Animal Poison Control Center. Toxicology and Poison Management Guidelines. American Society for the Prevention of Cruelty to Animals. https://www.aspca.org/pet-care/animal-poison-control

Regulatory & approvals

  • Central Drugs Standard Control Organisation (CDSCO), Government of India. Veterinary Drug Approval Registry, 1969–2026. Directorate General of Health Services. https://cdsco.gov.in/

Databases

  • Washington State University, College of Veterinary Medicine. Veterinary Clinical Pharmacology Laboratory (VCPL) — MDR1 Multidrug Sensitivity Database. https://vcpl.vetmed.wsu.edu/
Educational reference only
This information is provided for educational purposes and is not a substitute for professional veterinary advice, diagnosis, or treatment. Always consult a qualified veterinarian before administering any medication to your pet. Find a vet near you →

Related medicines

Other medicines in the same class (Thiazide diuretic).

Chlorothiazide
Rx
Inhibits Na+/Cl- cotransporter in the distal convoluted tubule, reducing sodium and chloride reabsorption and promoting diuresis. Also causes mild vasodilation and reduces renal calcium excretion (useful in hypercalciuria).
dogcat