Thyroid & hormones Dogs & Cats

Fludrocortisone for dogs and cats

A daily pill for Addison's disease. [1]

Last reviewed: October 2026 · 2 sources · see sources

Quick answerFludrocortisone (fludrocortisone acetate) is a prescription medicine for dogs and cats. It replaces mineralocorticoid hormones that control salt and potassium balance. The most common side effects: vomiting is uncommon.

Key facts

Generic nameFludrocortisone acetate
Common brand namesFlorinef
Used inDogs & Cats
TypeThyroid & hormones
Prescription?Prescription
Typical US priceNot listed (no reliable public source)

What it's used for

A daily pill for Addison's disease. [1]

How it works

It replaces mineralocorticoid hormones that control salt and potassium balance. [1]

Side effects and cautions

Common side effects: Vomiting is uncommon. At high doses: more thirst and urination, weight gain or weakness. [1]

Use with care: Requires regular electrolyte checks. [1]

Call your vet right away if your pet has trouble breathing, facial swelling, hives, collapse, or any side effect that is severe or getting worse.

About dosingDosing is your vet's call. We don't list doses because the right amount depends on your pet's weight, age, health and other medicines. Don't change a dose or stop a medicine without asking your vet, and never give a pet medicine meant for people unless your vet tells you to [2].

What it costs

We don't list a price for this one because we couldn't find a reliable public source. Ask your vet or pharmacy for a quote; prices depend on your pet's size, the dose and where you fill it.

Fludrocortisone FAQ

What is Fludrocortisone used for in dogs and cats?

A daily pill for Addison's disease.

What are the side effects of Fludrocortisone?

Vomiting is uncommon. At high doses: more thirst and urination, weight gain or weakness.

Does Fludrocortisone need a prescription?

Yes. It needs a prescription from a veterinarian.

How much Fludrocortisone should I give my pet?

Only your veterinarian can tell you. The right dose depends on your pet's weight, health and other medicines, so we don't list doses. Never give a pet a medicine prescribed for a person or another animal without asking your vet.

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This page is general information for pet owners, not veterinary advice. Talk to your vet about your own pet.

Sources (2) — tap to show
  1. VCA Animal Hospitals – Fludrocortisone acetate (veterinary drug handout)
  2. FDA – Frequently asked questions about animal drugs