Levothyroxine for dogs and cats
Replaces thyroid hormone in dogs with hypothyroidism (an underactive thyroid). [1]
Key facts
| Generic name | Levothyroxine |
|---|---|
| Common brand names | Thyro-Tabs Canine, Synthroid |
| Used in | Dogs & Cats |
| Type | Thyroid & hormones |
| Prescription? | Prescription |
| Typical US price | Not listed (no reliable public source) |
What it's used for
Replaces thyroid hormone in dogs with hypothyroidism (an underactive thyroid). [1]
How it works
It is a man-made form of the hormone the thyroid isn't making enough of. [1]
Side effects and cautions
Common side effects: Rare at the right dose. Signs of too much include restlessness, panting, weight loss and more thirst. [1]
Use with care: Not for pets with hyperthyroidism or untreated Addison's disease. Your vet will recheck blood levels to set the dose. [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.
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.
Levothyroxine FAQ
What is Levothyroxine used for in dogs and cats?
Replaces thyroid hormone in dogs with hypothyroidism (an underactive thyroid).
What are the side effects of Levothyroxine?
Rare at the right dose. Signs of too much include restlessness, panting, weight loss and more thirst.
Does Levothyroxine need a prescription?
Yes. It needs a prescription from a veterinarian.
How much Levothyroxine 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.