Methimazole For Cats Dosage: [Benefits-Side Effects]

Methimazole for Cats

Methimazole for cats also known as Thiamazole is an Antithyroid medication used to treat feline hyperthyroidism. So what is a safe Methimazole dosage for Cats?

Methimazole popular brands names Tapazole®, Felimazole® are mostly prescribed by the veterinarian to treat cats Hyperthyroidism. However, Felimazole is an FDA-approved drug for hyperthyroidism treatment in cats.

Knowing about the safe dosage of Methimazole for felines and other medication is essential for every kitty owner. Giving the medicine in the wrong amount may harm more than benefit.

Hyperthyroidism is a common health concern, and every cat can suffer from it; however, older and senior cats are more exposed. 

Proper and timely treatment is essential to control the risk of complications.

Hyperthyroidism leads cats to excessive weight loss, weakness, restlessness, abnormal appetite, behavioral changes, and cardiac problems.

This article is a comprehensive guide about Methimazole for Cats. You can use the table of content for smooth navigation. 

Methimazole for Cats

What is Methimazole for Cats?

Methimazole (Thiamazole) for cats is a thioureylenes antithyroid agent and a white, crystalline substance that is freely soluble in water. Its chemical formula is C4H6N2S, and its molecular weight is 114.16 Daltons. In cats, Methimazole inhibits the formation of thyroid hormones by inhibiting the incorporation of iodine into tyrosyl residues of thyroglobulin.

Felimazole Methimazole Dosage for Cats by Weight

According to the veterinarians, the safe dose of methimazole for cats is 2.5-5 mg per cat twice a day with a time gap of 12 hours. The dosage of Methimazole Transdermal Gel or Cream is 2.5 mg to the inside of the earflap twice a day. 

Methimazole or Felimazole should only be given to your kitty with vet advice.

What is the maximum dose of Methimazole for cats?

The amount of the medicine can be increased or decreased with the vet’s advice only depending on the illness severity. The maximum dose of methimazole for cats is 20 mg per day, single-dose 10mg, and should never exceed 10 mg single and 20mg/day.  

Methimazole 2.5mg for Cats

Methimazole 2.5mg for cats is considered the ideal and safe dose of Felimazole. Methimazole 2.5mg should be administered twice a day with the vet’s prescription to treat cat hyperthyroidism. 

How does Felimazole work?

The active ingredient in felimazole is Methimazole, an antithyroid drug that works by blocking the production of thyroid hormones and helps your kitty control Hyperthyroidism.

Forms of Methimazole for Felines

  • Felimazole is available in three tablet sizes: 1.25 mg, 2.5 mg, and 5 mg.
  • Thiafeline (Animalcare), available in 2.5 mg and 5mg  two tablet sizes
  •  Methimazole transdermal Gel is also available in 50 mg/ml.

Symptoms of of Hyperthyroidism in Cats

The most common symptoms of hyperthyroidism in cats are weight loss, weakness, restlessness, abnormal appetite, behavioral changes, vomiting, diarrhea, hyperactivity, increased thirst, frequent urinating, and cardiac problems.  

Hyperthyroidism in Cats

Felimazole Side effects of for Cats

Felamazole is an FDA-approved drug to treat hyperthyroidism in cats; however, it has some side effects like other medicine.

Some of the common side effects of Felimazole for feline are:

  • Behavioral changes
  • Weight loss
  • Change in appetite
  • Weakness
  • Agitation
  • Vomiting and diarrhea
  • Restlessness
  • Skin issues
  • Increased ALT 
  • Increased BUN

Side effects of Methimazole For Humans

The first thing you need to know is that Felimazole has minor to severe side effects for humans.

Methimazole is considered dangerous for pregnant and lactating women. Methimazole can cause congenital disabilities and birth defects because The drug crosses the placenta and concentrates in the fetus’s thyroid gland, and can also be found in breast milk. 

Pregnant and lactating women should avoid giving Felimazole to cats, or wear gloves when handling Felimazole tablets, cat litter, or grooming cats.

Sleeping with cats is also dangerous for pregnant women.

Some of the common side effects of methimazole in humans are:

  • vomiting 
  • Diarrhea
  • Itching
  • Upset stomach
  • Headache
  • Fever
  • Joint pain
  • Decrease in Red and white blood cells.

Contact your doctor immediately if you notice any of the above symptoms after contacting the Felimazole methimazole. 

How to give Felimazole methimazole to Cats?

Make sure to wash your hands after giving the Felimazole to your kitty.

Do not crush the Felimazole tablet to avoid contact with the drug.

Make sure to wear gloves before giving the medicine or cleaning your cat’s litter, or grooming your feline because a trace amount of the drug may be found in your kitty stool, urine, vomit, etc.

You can give the Felimazole tablet directly or with in the food.

Give liquid methimazole orally with a syringe.

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How Fast does methimazole work in cats?

Hyperthyroidism treatment in cats requires much time, and dont expect a too fast result of methimazole. Usually, the methimazole takes several weeks to reduce the thyroid hormone levels in your kitty blood and lower it down to the normal range. 

How long does it take methimazole to Start working?

Suppose you have recently started the treatment of your cat’s hyperthyroidism with Methimazole. In that case, it will require about 5-10 weeks and an average of 6 weeks to lower T4 thyroid hormone levels depending on the severity of the illness. 

What happens if I stop giving my cat methimazole?

The ideal way to give or stop methimazole to your cat is to follow your vet’s advice. Do not give or stop the medication without your vet’s advice. Self-medication and incorrectly offering any drugs, including Felimazole is, toxic.

Does methimazole make cats Sleepy?

Some side effects are associated with methimazole for cats, such as vomiting, diarrhea, lack of appetite, and weight loss. Due to these side effects, your cat may appear sleepy when you give  Felimazole to your kitty. 

Can cats recover from Hyperthyroidism?

Chances of recovery of hyperthyroidism in cats depend on the illness’s severity and treatment. If your cat is diagnosed early with hyperthyroidism and you start treatment under the supervision of a professional veterinarian, there are good chances of your feline recovery from hyperthyroidism. 

What happens if you don’t treat Hyperthyroidism in cats?

Delaying in the treatment of feline hyperthyroidism can lead to fatal health issues such as heart problems and liver issues. 

Ensure a routine checkup of your tom or queen for timely diagnosis of any health issue. 

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