Methimazole oral tablet dosage: A detailed guide

Key takeaways

• The typical starting dosage of methimazole for adults with hyperthyroidism varies based on the severity of the condition, ranging from 15 milligrams (mg) for mild cases to 60 mg for severe cases, divided into three daily doses.
• For children, the starting dosage is typically 0.4 mg per kilogram of body weight daily, divided into three doses.
• After the starting dosage, doctors will usually lower the dosage to a maintenance level. For children, this is typically half of the starting dosage.

Overview

This article describes methimazole oral tablet’s dosages and strengths and gives details on how to take it. You’ll also find information on cost savings and coupon options for methimazole.

If you want to know more about methimazole oral tablet, see this overview article. It covers details about the drug’s uses, its side effects, and more.

Methimazole oral tablet is a generic medication. It’s not available in a brand-name version.

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Form and strengths of methimazole

Methimazole oral tablet comes as follows:

• Form: oral tablet that you swallow
• Strengths: 5 milligrams (mg), 10 mg

Methimazole dosage

This article describes the recommended dosages for methimazole oral tablet. The drugmaker provides these dosages. In some cases, doctors may adjust your dosage from those shown below.

If your doctor prescribes this medication, you should follow the dosage they prescribe. Your doctor will determine the dosage that best meets your needs. Do not change your dosage of methimazole oral tablet without your doctor’s recommendation.

Usual recommended dosages of methimazole in adults

Doctors typically prescribe a recommended starting dosage. Then, they’ll lower it to a maintenance dosage that you’ll take for the remainder of your treatment.

Methimazole oral tablet is approved for use in adults to treat hyperthyroidism. Your doctor will prescribe the dosage that’s right for you, which depends on the severity of your condition. It’s likely that after some time, they may adjust your dosage to get the desired outcome.

Dosage for hyperthyroidism

The table here shows dosages for adults in milligrams (mg).

Dividing the doses throughout the day helps keep a steady level of the drug in your body. This can help it work effectively.

Dosage of methimazole in children

Methimazole oral tablet is approved for use in children to treat hyperthyroidism. But the prescribing information doesn’t provide age ranges for children. If your child’s doctor prescribes methimazole oral tablet, they’ll discuss its use and the right dosage for your child.

The typical starting dosage of methimazole oral tablet in children is 0.4 mg per kilogram (kg) of body weight per day. For reference, 1 kg is about 2.2 pounds (lb). You’ll divide your child’s dose into three equal doses, and they’ll take one dose every 8 hours.

For example, assume a doctor prescribes methimazole for a child weighing 25 kg (about 55 lb). The child’s dosage would be 10 mg per day, to be divided into three equal doses. The child would take one dose every 8 hours.

The maintenance dosage of methimazole in children is half of their starting dosage. If a child took a starting dosage of 10 mg per day, their maintenance dosage would be 5 mg per day. They would take the dose once per day. Or their dose would be divided into equal doses to take throughout the day as prescribed.

Dosage adjustments for methimazole

Your doctor will prescribe a dosage of methimazole oral tablet based on several factors. These include:

• the specific condition being treated and how severe it is
• your age
• other health conditions you may have

Missed dose of methimazole

Talk with your doctor or pharmacist right away if you realize you forgot to take a dose of methimazole oral tablet. They may advise you to take the missed dose. Or they may advise you to skip it and take your next dose as scheduled.

For tips on how to plan your doses of methimazole oral tablet and avoid missing a dose, read this article. You could also try:

• downloading a reminder app on your phone
• setting an alarm
• putting a note where you’ll see it, such as on your calendar, bathroom mirror, or bedside table

Frequently asked questions

Here are answers to some commonly asked questions about methimazole oral tablet and its dosage.

Is there a 2.5 mg dose of methimazole?

Yes, a doctor might prescribe a 2.5 milligram (mg) dose of methimazole to treat hyperthyroidism. This dose could be prescribed as a starting dose in children. Children’s dosages are based on their body weight in kilograms (kg).

It’s also possible to be prescribed the 2.5 mg dose for maintenance of hyperthyroidism in adults. The maintenance dosage range of methimazole in adults is 5 to 15 mg per day. This may be taken as one dose, or it could be divided into multiple doses to be taken two or three times per day.

This dose is not available as a separate tablet but can be made by splitting a 5 mg tablet as directed by your doctor.

Your doctor or pharmacist can provide more details about your dosage.

When is the best time of day to take methimazole?

Ask your doctor or pharmacist about the best time of day to take your methimazole doses. You’ll typically start by taking each of the three daily doses every 8 hours.

Your doctor or pharmacist can suggest a dosing schedule that fits your needs. For example, they may suggest taking a methimazole oral tablet at 6 a.m., 2 p.m., and 10 p.m. It’s important to be consistent when taking your medication, so consider taking it at regular times each day to encourage a routine.

Over time, your doctor may lower your methimazole dose. This may also instruct you to take a dose once or twice per day rather than three times per day. In this case, your doctor will tell you the best time of day to take your methimazole dose.

Talk with your doctor or pharmacist to learn more.

Is methimazole taken long term?

Yes, your doctor may prescribe methimazole oral tablet as a long-term treatment. The duration of your methimazole treatment will depend on your condition and its severity. If you and your doctor determine that it’s safe and effective for your condition, you’ll likely take it long term.

If you have questions about how long you should take methimazole oral tablet, talk with your doctor.

Methimazole coupon

Visit this page to access Optum Perks coupons and get price estimates for methimazole when you use the coupons. These coupons can provide significant savings on your prescription costs. 

Note: Optum Perks coupons cannot be used with insurance copays or benefits.

Overdose of methimazole

It’s important that you do not take more methimazole oral tablet than your doctor prescribes. Doing so can lead to harmful effects.

Symptoms of methimazole overdose

Symptoms of an overdose can include:

• nausea
• vomiting
• headache
• fever
• joint pain
• itching
• aplastic anemia, which affects red blood cells
• agranulocytosis, which affects a type of white blood cell

What to do if you take too much methimazole

If you think you’ve taken too much methimazole, call your doctor or pharmacist right away. Or you could call 800-222-1222 to speak with someone at America’s Poison Centers. You can also use its online resource. If you have severe symptoms, call 911 or a local emergency number immediately. You can also go to the closest emergency room.

Disclaimer: Optum Perks has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or another healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.