Vet prescription required in checkout

Felimazole Tablets 2.5mg

You save 54%
Vet prescription required in checkout
You save 54%

Felimazole Tablets 2.5mg

Felimazole Tablets are used for long-term treatment of feline hyperthyroidism in cats.
Standard Retail Price £0.42
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Felimazole 2.5mg tablets for cats is a medication used to treat and manage hyperthyroidism (overactive thyroid). Hyperthyroidism is where the thyroid gland produces too much of the thyroid hormones.

Each round, coated pink, sugar-coated Felimazole 2.5 tablet contains 2.5mg of the active ingredient Thiamazole. Thiamazole acts by blocking the biosynthesis of thyroid hormone in vivo; it works by inhibiting the binding of iodine to the enzyme thyroid peroxidase.

Common symptoms often seen is cats suffering with hyperthyroidism include; irritability, weight loss (usually despite an increased appetite), increased thirst, restlessness/ hyperactivity, matted or unkempt coat and an increased or rapid heart rate.

Hyperthyroidism is a common disease in older cats and Felimazole 2.5mg tablets have been proven as an effective treatment which is often used long-term.

The dose rate of Felimazole will be determined by your veterinary surgeon depending on how well your cat responds to the treatment. However, Felimazole tablets should not be crushed or broken; they should always be given whole.

Felimazole tablets are also available at 1.25mg and 5mg doses for different breeds and sizes of cat.

Special Instructions

Do not use in cats suffering from systemic disease such as primary liver disease or diabetes mellitus.

Do not use in cats showing signs of autoimmune disease.

Do not use in animals with disorders of white blood cells, such as neutropenia and lymphopenia.

Do not use in animals with platelet disorders and coagulopathies (particularly thrombocytopenia).

Do not use in cats with hypersensitivity to thiamazole or the excipient, polyethylene glycol.

Do not use in pregnant or lactating females.

As thiamazole can cause haemoconcentration, cats should always have access to drinking water.

Wash hands after use. As thiamazole is a suspected human teratogen, women of child-bearing age and pregnant women should wear gloves when handling litter of treated cats. Pregnant women should wear gloves when handling the product.


If you see the "prescription required" sign next to an item you’d like to order, it means the item can only be issued with a prescription. While you can add these items to your shopping cart and pay for them along with other non-prescription products, we can’t dispatch them until we’ve received a prescription.

Delivery Info

For orders over £39 postage is free. For orders under £39 we charge £2.99.

For Light items (under 2kg) our standard method is Royal Mail First Class (there are a few exceptions, so if in doubt check our Delivery page).

To get it faster you can upgrade Light items to a Guaranteed Next Day Courier service, Saturday Courier or even before 12 noon services. There's a small fee, but if you're in a hurry they are worth considering. To qualify for next working day delivery, orders must be placed before 12 Noon Monday to Thursday. There is no standard Saturday courier delivery.

Heavy items weighing 2kg and more are sent via courier. If ordered before noon Monday to Thursday, Heavy items will be delivered next working day. Heavy items ordered after 12 Noon Friday, or anytime Saturday and Sunday will dispatched on Monday for a Tuesday delivery.

All exceptions to these guidelines are noted in the product description.

For more information, view our Delivery page.

Service Reviews (1100)
Independent Customer Feedback

Felimazole Tablets 2.5mg

4.9/ 5
(1100 customer reviews)
  1. 4
    "Good service. The correct and fulfilled prescription arrived quicker than expected , brought at a much more acceptable price than the vets!! Thank you"
    Review by / (Posted on
  2. 5
    "I placed order and it was dispatched next day. Cannot fault service. I would and will be buying from them again."
    Review by David Jones / (Posted on
  3. 5
    "Excellent service will be using them again and would highly recommend"
    Review by / (Posted on
  4. 5
    "Fast, friendly and excellently priced. The process of ordering, submitting copies of prescriptions and payment were all simple, and the order arrived faster than expected too. Will definitely use again in the future!"
    Review by Sie Barlow / (Posted on
  5. 5
    "great service"
    Review by / (Posted on
View all 1100 customer reviews

Vet prescription required in checkout

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