5 Best Pet Thyroid & Hormone Medications - Sept. 2026

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PROS

Commonly prescribed for Addison's Disease, a condition that affects hormonal production of the adrenal system.
Can be taken by dogs or cats.
Reduces inflammation, and is well-tolerated by most pets.

CONS

Some pets may experience upset digestive system and tiredness.
An increase in thirst and hunger, and frequent urination, are common side effects.

Vetoryl

Capsules for Dogs

Controls Canine Cortisol

Despite possible side effects, this drug is worth the risks for dogs that are suffering from Cushing's Disease, which could progress to debilitating symptoms and death if left untreated.

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PROS

Controls Cushing's Disease in dogs, a disease that causes the pituitary gland to make an abundance of adrenocorticotropic hormone (ACTH), which increases cortisol.
Disease leads to weight gain, major thirst and hunger, and even death if left untreated, Drug is effective at controlling progression in most dogs.

CONS

Digestive symptoms and lethargy are common side effects.
Major diarrhea, depression, or unresponsiveness could be signs of a severe reaction that require prompt veterinarian intervention.

Incurin (Estriol)

Tablets for Dogs

For Incontinence

This medication helps female dogs with post-spay incontinence, and is well-tolerated by most that take it.

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PROS

Used to treat urinary incontinence in female dogs that results from them being spayed.
Works by targeting estrogen changes that can lead to incontinence following spay surgery.
Works well for most dogs with few side effects.

CONS

Can cause stomach upset.
Not for male dogs, or females dogs that are not spayed or are pregnant.

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First Reviewed

November 09, 2021

Models
considered

Hours
researched

Written by Jennifer Manfrin

Updated August 2025

Just like their human owners, dogs and cats can develop thyroid and hormonal problems. Conditions like Cushing's and Addison's diseases, hypothyroidism and hyperthyroidism result in symptoms like weight gain or loss, changes in appetite and behavior, and an overall decline in health. Some hormonal issues affect the reproductive system, and can cause problems such as incontenence. The good news is that there are medications that can reduce or replace hormones and greatly improve symptoms. If your dog or cat is presenting with symptoms that could indicate and thyroid and hormone imbalance, schedule a visit with your veterinarian. Once diagnosed, your vet will prescribe a type of hormonal medication that you most likely will be able to conveniently purchase online, which may also save you some money.

Best Pet Thyroid & Hormone Medications

Pros and Cons

Pros and Cons

Pros and Cons

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