Approved by FDA in May 2009, Felimazole contains methimazole as the active ingredient. Unlike the methimazole products for people, Felimazole has been shown to be safe and effective in cats when used according to the directions on the label. The drug’s label provides dosing and safety information specific to cats.

What is the generic name for methimazole?

Methimazole (Tapazole) is an anti-thyroid medication. It blocks the thyroid gland from making thyroid hormones.

Why is my cat taking Felimazole?

FELIMAZOLE Coated Tablets contain the active ingredient methimazole and are given to your cat every day to block the production of thyroid hormones. Hyperthyroidism can be treated very successfully, especially since very few cats develop cancerous growths of the thyroid gland.

Is there an alternative to methimazole for cats?

It is available through compounding pharmacies if at all. Another approach for cats who cannot take methimazole involves a combination of potassium iodate and a heart medication called “propranolol.” Potassium iodate blocks the thyroid gland’s uptake of iodine.

Is methimazole safe for cats?

Methimazole (oral and transdermal) is a safe and effective medication for the treatment of feline hyperthyroidism.

What is the difference between methimazole and Carbimazole?

Carbimazole has a higher molecular weight than methimazole, so 5 mg of carbimazole is equivalent to 3 mg of methimazole. The starting dose for carbimazole is 5 mg every 8 to 12 hours.

Does methimazole slow heart rate?

Methimazole-treated G2K-1 C rats showed reductions in heart rate, ventricular weight, ventricular/body weight ratio and mortality in comparison with rats not treated with methimazole.

What is the life expectancy of a cat with hyperthyroidism?

The average age of cats with hyperthyroidism is approximately 12 years and about 5% of hyperthyroid cats are younger than 10 years of age.

How long can a cat live on methimazole?

When cats with preexisting renal disease were excluded, median survival time for cats treated with methimazole alone (2.0 years; interquartile range [IQR], 1 to 3.9 years) was significantly shorter than median survival time for cats treated with 131I alone (4.0 years; IQR, 3.0 to 4.8 years) or methimazole followed by …

What happens if I stop giving my cat thyroid medicine?

Methimazole may produce side effects in cats including depression, vomiting and lack of appetite. These signs usually resolve without stopping the medication. A more serious side effect is the development of low blood cell counts which are more likely to develop during the first 3 months of treatment.

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Can methimazole cause kidney problems in cats?

13 If a cat treated with methimazole experiences a severe drop in GFR and develops overt renal failure, the clinician must begin the difficult course of balancing hyperthyroidism and its effects against the effects of renal failure.

How much methimazole can a cat have?

It is currently recommended that oral methimazole be administered at a dose of 2.5 to 5 mg per cat every 8 to 12 h (1,2). Following this regimen, treated animals will usually reach a euthyroid state within 7 to 14 d. The dose of methimazole can then be adjusted accordingly to maintain a normal serum T4.

What is the best food to feed a cat with hyperthyroidism?

It is best to feed: Canned or raw diets, that contain little to no fruits, vegetables, or grains. Any canned cat food is better than any dry, which contains too much carbohydrate and plant-based protein.

Can hyperthyroidism in cats cause death?

Feline hyperthyroidism is a common endocrine disorder in older cats, caused by the overproduction of thyroid hormone. Left untreated, hyperthyroidism can result in heart failure and other complications, and can even lead to death.

What are the side effects of methimazole in cats?

The most common side effect is upset of the digestive tract. Up to 20% of cats may experience nausea, vomiting, loss of appetite and just not feel well. Usually this is self-limiting and most cats stop vomiting and begin to feel better without any change to the medication.

What are the long term effects of methimazole?

Long-term use of Tapazole may lead to a remission of hyperthyroidism. Grave’s disease is the most common cause of hyperthyroidism.

Can methimazole cause heart palpitations?

Methimazole is a thioamide-derived antithyroid drug used to treat hyperthyroidism, a condition that can lead to weight loss, heat intolerance, hypertension, heart palpitations, diaphoresis, anxiety, insomnia, and hyperhidrosis.

Can methimazole lower your blood pressure?

In summary, the results of this study demonstrate that treatment with methimazole: (a) prevents and reverses LRM hypertension in rats, and (b) decreases pressor responsiveness to vasoconstrictor substances that may play a role in the prevention and reversion of hypertension following methimazole administration in LRM …

Does hyperthyroidism cause tachycardia?

Sinus tachycardia is the most common rhythm disturbance and is recorded in almost all patients with hyperthyroidism. An increase in resting heart rate is characteristic of this disease.

Does methimazole cause liver damage?

Methimazole is also capable of causing clinically apparent, idiosyncratic liver injury. The onset of hepatotoxicity is usually within 2 to 12 weeks of starting and the pattern of enzyme elevations is typically cholestatic or mixed, although hepatocellular patterns have also been described.

Does methimazole increase TSH levels?

Conclusions: In patients with Graves’ disease who are treated with MMI for at least 2 years and become euthyroid, the occurrence of elevated serum TSH concentrations during MMI treatment is a favorable indicator for long-term remission and is independent of multiple other factors including TSAb status, duration of MMI …

How long should you stay on methimazole?

For methimazole For treatment of hyperthyroidism (overactive thyroid): Adults and teenagers—At first, 15 to 60 milligrams (mg) a day for up to six to eight weeks. Later, your doctor may want to lower your dose to 5 to 30 mg a day. This may be taken once a day or it may be divided into two doses a day.

Does hyperthyroidism in cats shorten lifespan?

Most cats with uncomplicated hyperthyroidism will live several years following treatment of hyperthyroidism, unless they develop another disease.

Does methimazole cause liver damage in cats?

Other complications include appetite loss, vomiting, weakness, and liver damage. Some of the less common side effects include anemia, lymph node swelling, abnormal bleeding, and jaundice. If your cat has any of these symptoms when taking methimazole, you need to see your veterinarian right away.

How can I help my hyperthyroid cat gain weight?

Canned foods are generally the best choice when seeking to provide a high-protein, low-carbohydrate diet. Dry foods tend to be energy (read calorie) dense. Also, because starch is necessary to make the kibble, dry foods tend to have greater carbohydrate concentrations (carbohydrate > 25% on a dry-matter basis).

How long does it take for methimazole to work in cats?

If your pet has other diseases, one treatment may be better for your cat than another. The anti-thyroid pill is methimazole, also known as Tapazole. Methimazole is given one to three times daily and must be continued life long. It takes several weeks for methimazole to reduce blood thyroid hormone levels to normal.

Can a cat recover from hyperthyroidism?

The good news is that the prognosis for feline hyperthyroidism is not all bad. In fact, when treated early and effectively, many cats can fully recover and have normal thyroid activity restored.

Are cats with hyperthyroidism in pain?

In addition, hyperthyroidism can cause hypertension or high blood pressure, and result in damage to the eyes, kidneys, and brain. Cats with untreated hyperthyroidism can also endure pain and a lower quality of life due to the symptoms of the disease.

Can you crush Felimazole for cats?

Do not break or crush the tablets. Trace amounts of Felimazole can be found in a treated cat’s feces (stool) and bodily fluids, so wear gloves when you scoop your cat’s litter or if you have contact with your cat’s feces, urine, or vomit. Also wear gloves when you handle broken or moistened Felimazole tablets.

Does Felimazole make cats sleepy?

In a US field study with 113 cats, the most common adverse reactions included change in food consumption (increase or decrease), lethargy, vomiting, diarrhea/loose stool, skin lesions, and abnormal vocalization.

What foods should be avoided with hyperthyroidism?

  • iodized salt.
  • fish and shellfish.
  • seaweed or kelp.
  • dairy products.
  • iodine supplements.
  • food products containing red dye.
  • egg yolks.
  • blackstrap molasses.