Methimazole Tablets for Cats - Treat Hyperthyroidism, 5 mg

Antithyroid Tablets to Manage Hyperthyroidism in Cats

Product Description

Methimazole 5mg is a prescription antithyroid medication used to manage hyperthyroidism in cats. It works by reducing the thyroid gland's ability to produce excess hormone, helping bring metabolic function back to a normal range. Since it manages rather than cures the condition, most cats stay on it long term. It is FDA-approved for veterinary use in cats and is widely regarded as the antithyroid treatment of choice in feline medicine.

Benefits

• Controls Feline Hyperthyroidism: Reduces overproduction of thyroid hormone, helping manage symptoms like weight loss, increased appetite, and hyperactivity in affected cats.
• Restores Normal Thyroid Levels: When dosed correctly and consistently, methimazole is highly effective at bringing thyroid hormone levels back within a healthy range.
• As Effective as Surgery or Radiotherapy: Used properly, methimazole delivers results comparable to radioactive iodine therapy or surgical thyroidectomy, at a much lower cost.
• Helps Assess Kidney Function: Normalising thyroid levels with methimazole first allows vets to evaluate how the kidneys respond before committing to any permanent treatment option.
• Available in Multiple Forms: Beyond tablets, methimazole can be compounded into flavored liquids, chewables, or transdermal gels for cats that are harder to medicate orally.
• Non-Addictive for Long-Term Use: Methimazole carries no risk of dependency, making it a practical and safe choice for cats requiring ongoing thyroid management.

Ingredients

Active Ingredients

Methimazole

How to Use

Methimazole is a prescription-only medication. A valid prescription from a licensed veterinarian is required to purchase this medicine.

Please follow your veterinarian's specific instructions for dosage, frequency, and duration of treatment for your cat.

Disclaimer: Dosage and administration of this medication must be determined by a licensed veterinarian. Always consult your veterinarian before administering or adjusting any prescription medication for your pet.

Getting your cat to take a tablet does not have to be a struggle. Tucking the tablet into a pill pocket or pill wrap makes the whole experience far less stressful for your cat and for you.

Shop Pill Pockets for Cats

Additional Information

Precautions

• Not for Pregnant or Breeding Cats: Methimazole must not be used in pregnant, nursing, or breeding cats due to risk of serious developmental harm.
• Caution with Organ Disease: Cats with autoimmune, liver, kidney, or blood clotting issues need close veterinary supervision on this medication.
• Avoid in Allergic Cats: Do not use in cats with a known allergy to methimazole, carbimazole, or polyethylene glycol, as serious reactions may occur.
• Regular Blood Monitoring Required: Blood tests are needed before starting and every 2 to 3 weeks for the first 3 months, then every 3 to 6 months once stable.
• Drug Interactions to Note: Methimazole may interact with several medications including beta-blockers, digoxin, and phenobarbital; always keep your vet informed of everything your cat takes.
• Do Not Break or Crush Tablets: Tablets should be handled whole with protective gloves, and hands must be washed thoroughly after every handling to avoid skin contact.

Possible Side Effects

• Common Early Side Effects: Vomiting, reduced appetite, and tiredness are most frequently seen in the first three months and may settle with continued treatment.
• Facial Itching (Stop Medication): Head or facial itching signals poor tolerance to methimazole and tends to return if restarted; an alternative thyroid treatment will likely be needed.
• Rare Liver Disease: Serious liver disease affects less than 2% of cats; watch for complete loss of appetite, extreme lethargy, or yellowing of the skin, gums, or eyes.
• Blood Cell Changes: Changes in blood cell counts occur in less than 4% of cats; regular blood tests help catch these early before they require a treatment change.
• Other Rare Effects: Less common reactions include immune-mediated disorders, skin lesions, elevated liver enzymes, anemia, diarrhea, and thrombocytopenia in some cats.

Storage Information

• Store at Room Temperature: Keep methimazole tablets in a dry, dark place at room temperature, protected from both light and moisture at all times.
• Keep Away from Children: Store in a secure location out of children's reach, as methimazole can cause serious adverse effects if handled or ingested by humans.
• Keep Away from Other Pets: Make sure other animals in the household cannot access the storage area to prevent accidental ingestion of this medication.

Note: For generic medications, the product image shown may not reflect the actual item received. Generic medications can vary in size, color, and shape between orders depending on the manufacturer. Additionally, your medication may arrive packaged in a HardyPaw Pharmacy vial.

Shipping & Return

We offer ground, express, and priority delivery; see our shipping policy for details.

For return instructions or product concerns, please refer to our detailed refund policy.

Prescription items are NON-RETURNABLE and NON-REFUNDABLE.

Frequently Asked Questions

Q1: What is methimazole 5mg used for in cats?

Ans: Methimazole 5mg is prescribed to manage feline hyperthyroidism, where an overactive thyroid gland throws the body's metabolism off balance. It brings thyroid hormone levels back under control to restore normal function. Since it manages rather than cures the condition, most cats need it lifelong.

Q2: How does methimazole work to control hyperthyroidism in cats?

Ans: Methimazole blocks several steps involved in thyroid hormone production, reducing the amount the thyroid gland can make. It does not clear hormones already in circulation, so noticeable improvement may take days to weeks after starting treatment. Consistent dosing is key to keeping levels controlled.

Q3: How long does my cat need to stay on methimazole?

Ans: Hyperthyroidism in cats does not go away on its own, so methimazole is usually a lifelong commitment. Without it, the thyroid gets overactive again fairly quickly. Pet owners who struggle with daily tablets can speak to their vet about other treatment paths that offer a more permanent solution.

Q4: What monitoring does my cat need while on methimazole?

Ans: Blood tests are needed before starting treatment and every 2 to 3 weeks during the first 3 months to check thyroid levels and watch for any effects on blood cells or organ function. Once the dose is stable, thyroid levels should be rechecked every 3 to 6 months.

Q5: What should I do if my cat develops facial itching after starting methimazole?

Ans: Facial or head itching is a sign your cat is not tolerating methimazole well. This reaction tends to come back if the medication is restarted, so stop use and contact your vet promptly. Your vet may recommend switching to radioactive iodine therapy or surgery as an alternative.

Clinical Research

https://journals.sagepub.com/doi/full/10.1016/S1098-612X%2802%2900095-5

https://onlinelibrary.wiley.com/doi/full/10.1111/j.1939-1676.2011.00799.x

https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1365-2885.1991.tb00850.x