Methimazole

Methimazole is the most common medication prescribed to treat feline hyperthyroidism. 

This pet medication works to reduce the levels of thyroid hormone by decreasing thyroid hormone synthesis. 

This is considered an antithyroid agent used to manage hyperthyroidism. Hyperthyroidism is the overactivity of the thyroid gland.

What is hyperthyroidism?

Hyperthyroidism is when there is overproduction of the thyroid hormone leading to thyroid hormone levels in the blood to be too high. 

People who have hyperthyroidism are said to have an "overactive thyroid". 

The thyroid hormone is produced by the thyroid gland and released into the bloodstream. It interacts with almost all body cells, causing them to increase their metabolic activity. 

This abnormally high level of thyroid hormone typically speeds up the body's metabolism. Metabolism is the physical processes that create the substances and generate the energy needed for cell function, growth, and division. 

hyperthyroidism in pets

How about Kombucha?


What does the thyroid hormone do?

Cells respond to the thyroid hormone with an increase in metabolic activity. 

The thyroid hormone stimulates cells causing major body functions to speed up. 

As a result...

  • Your body increases the use of proteins, fats, and carbohydrates


  • Skeletal muscles work more efficiently


  • Your breathing rate increases


  • Your heart rate increases


  • Mental alertness and thinking skills are sharpened


  • there is an increase in muscle tone in the digestive system to help to move food through the digestive system

Does this effectively treat feline hyperthyroidism?

This is commonly used to treat hyperthyroidism in cats. 

Some advantages to treatment include...

  • Control of thyroid disease is achieved only while the pet is on medication so that if there is any problem with exacerbation of poor kidney function, then the treatment can be stopped.


  • If an occasional dose is skipped, no harm is done.


  • Side effects are relatively uncommon.


  • No hospitalization is required.


  • If after the first 3 months of therapy no side effects have been encountered, the chance of side effects occurring thereafter is substantially reduced.


  • Medication is inexpensive relative to radiotherapy or surgery.

Side effects of methimazole

Most side effects occur during the first 3 months of therapy. 

Some common side effects include..

  • anorexia


  • depression


  • vomiting

More rare side effects include..

  • agranulocytosis


  • hepatopathy


  • thrombocytopenia


  • bleeding

Another rare side effect is a small percentage of cats self mutilate their face and neck through scratching. If this happens, you probably need to discontinue treatment with Methimazole. 

This should be used with caution and with extra monitoring in cats with liver disease, autoimmune disease or pre-existing blood abnormalities. 


Compounding pet medications

Sometimes medication is designed for people and not specifically designed for your pet. A compounding pharmacy can create a medication convenient for a cat or dog. 

The compounding pharmacist reformulates the medication so that your pet will likely be more willing to take it. 

If your veterinarian needs a flavored oral liquid or a particular sized capsule, you might check out a compounding pharmacy. 

The methimazole creams are rubbed on the inside of the cats ears 1 to 2 times a day. 

The cream seems to be very affective and the cat usually stays on the medicine for the rest of its life. 


› Methimazole

Recent Articles

  1. Hormone Replacement Products

    Dec 28, 15 06:44 PM

    Hormone replacement products. Do you know the difference between synthetic hormones (premarin, esclim, climara, alora, estrace vaginal cream, menostar, premphase, prempro) and natural hormones...

    Read More

  2. Bioidentical Hormones, Natural Hormone Replacement Therapy

    Dec 28, 15 06:41 PM

    Bioidentical hormones, correct hormone imbalance with hormone replacement therapy, seeing dramatic improvements in your overall well-being...

    Read More

  3. Probiotic Supplements, Natural Creations, Enterobiotic Group

    Dec 28, 15 06:40 PM

    Probiotic supplements are basically good bacteria that help crowd out the bad bacteria in the intestinal tract acting as a barrier of protection against infection causing organisms

    Read More