If you have seizures or migraine, your doctor might suggest Topamax (topiramate) as a treatment option for you.

Topamax is a prescription medication that’s used in adults and some children to prevent migraine headaches and to treat certain types of seizures caused by epilepsy.

Topamax is used to treat the following types of seizures:

Topamax belongs to a group of medications called anticonvulsants.

This article describes the dosages of Topamax, including its forms, strengths, and how to take the drug. To learn more about Topamax, see this in-depth article.

Note: This article covers Topamax’s typical dosages, which are provided by the drug’s manufacturer. But when using Topamax, always take the dosage that your doctor prescribes.

The information below discusses dosages of Topamax.

What are the forms of Topamax?

Topamax comes in two forms:

  • coated tablets that you swallow
  • sprinkle capsules that you can swallow whole or open and sprinkle on a small amount of soft food and swallow

What strengths does Topamax come in?

Topamax tablets come in four strengths: 25 milligrams (mg), 50 mg, 100 mg, and 200 mg.

Topamax sprinkle capsules come in two strengths: 15 mg and 25 mg.

What are the typical dosages of Topamax?

Your dosage of Topamax may depend on:

  • your age
  • your weight
  • the condition being treated
  • the severity of your condition
  • if you’re taking other medications with Topamax
  • if you have other health conditions, such as kidney disease

Typically, your doctor will start you on the lowest dosage of Topamax. Then, they’ll slowly increase your dosage over time to reach the right amount for you.

The maximum dosage, or highest dosage, of Topamax you’ll be prescribed depends on your condition and how well you tolerate the drug. Your doctor will ultimately prescribe the smallest dosage that provides the desired effect.

The information below describes dosages that are commonly used or recommended. But be sure to take the dosage your doctor prescribes for you. Your doctor will determine the best dosage to fit your needs.

Dosage for preventing migraine headaches

The recommended dosage of Topamax for migraine is 50 mg taken two times per day. Your doctor will have you start your treatment by taking 25 mg in the evening for 1 week to see how your body reacts to the drug. Then, they’ll gradually increase your dose each week for 4 weeks until you reach the maximum dosage of 50 mg taken twice per day.

Slowly increasing your Topamax dosage over several weeks allows your doctor to see how well you tolerate the drug. It also helps your body get used to the medication.

Below is the typical dosage schedule for migraine prevention:

  • Week 1: 25 mg in the evening
  • Week 2: 25 mg in the morning and 25 mg in the evening
  • Week 3: 25 mg in the morning and 50 mg in the evening
  • Week 4: 50 mg in the morning and 50 mg in the evening

Your doctor may increase your dosage even more slowly if you experience side effects. They’ll talk with you about your dosing schedule and the maximum dosage of Topamax you’ll take daily.

Dosage for treating seizures

Your doctor will start you on the lowest dose of Topamax, which is 25 mg taken daily. They’ll gradually increase your dose until you reach the highest dose that’s right for you, based on the factors mentioned above. In some cases, if you experience side effects or have certain health conditions, your doctor may adjust your dose to reduce the risk of serious side effects.

Your dosage for treating seizures will depend on whether you take Topamax by itself or with other drugs. See below for details.

Topamax dosage when used alone

Topamax can be used on its own to treat partial onset seizures and generalized tonic-clonic seizures.

When taken alone, the maximum Topamax dosage for seizures is 200 mg taken twice per day for a total of 400 mg daily. You’ll take one dose in the morning and one in the evening.

Your doctor will start you on the lowest dose of Topamax and slowly increase your dose until you reach the maximum recommended dosage.

Below is the typical dosage schedule for treating seizures:

  • Week 1: 25 mg in the morning and 25 mg in the evening
  • Week 2: 50 mg in the morning and 50 mg in the evening
  • Week 3: 75 mg in the morning and 75 mg in the evening
  • Week 4: 100 mg in the morning and 100 mg in the evening
  • Week 5: 150 mg in the morning and 150 mg in the evening
  • Week 6: 200 mg in the morning and 200 mg in the evening

Topamax dosage when used with other seizure drugs

Topamax may be used with other medications to treat partial onset seizures, generalized tonic-clonic seizures, or seizures linked to Lennox-Gastaut syndrome.

During the first week of treatment, your doctor will start you on a low dose, such as 25 mg to 50 mg per day. This will allow your doctor to see how your body reacts to the drug. Then, they’ll gradually increase your dose over several weeks until you reach the dose that’s right for you. The maximum recommended dosage is 400 mg per day.

  • For partial onset seizures and seizures linked to Lennox-Gastaut syndrome, the recommended dosage is 200 mg to 400 mg per day. This is taken as two doses, one in the morning and one in the evening.
  • For generalized tonic-clonic seizures, the dosage is 200 mg taken twice per day for a total of 400 mg per day. You’ll take one dose in the morning and one in the evening.

What’s the dosage of Topamax for children?

The Topamax dosage for children depends on the condition being treated, your child’s age, and their body weight.

Topamax dosage for preventing migraine headaches

Topamax is used to prevent migraine headaches in children ages 12 years and older. The dosage is the same as it is for adults. See the “Dosage for preventing migraine headaches” section above for details.

Topamax dosage for treating seizures

For treating seizures, the dosage for children depends on whether Topamax is used alone or with other drugs. See below for details.

Topamax dosage when used alone in children ages 2 years to 9 years

Topamax can be used on its own to treat partial onset seizures and generalized tonic-clonic seizures in children ages 2 years and older.

For children ages 2 years to 9 years, the Topamax dosage is based on weight.

The starting dosage is 25 mg taken in the evening for 1 week. If your child tolerates this dosage, the Topamax dosage is increased to 25 mg taken twice per day for 1 week. After this, the dosage is gradually increased by 25 mg to 50 mg over several weeks until the maximum dosage for their weight is reached. The dose is increased gradually to lower the risk of side effects with the drug.

The table below shows the recommended dosage of Topamax based on your child’s weight in kilograms (kg).*

WeightMaintenance dosage range per day, divided into two doses (morning and evening)
Up to 11 kg150 mg to 250 mg
12 kg to 22 kg200 mg to 300 mg
23 kg to 31 kg200 mg to 350 mg
32 kg to 38 kg250 mg to 350 mg
38 kg and greater250 mg to 400 mg

* One kg equals about 2.2 pounds.

The maximum recommended dose is 400 mg per day. Your child’s doctor will determine what their dose should be based on their weight in kg.

Topamax dosage when used alone in children ages 10 years and older

For treating partial onset and generalized tonic-clonic seizures in children ages 10 years and older, the dosage is the same for children as it is for adults.See the “Topamax dosage when used alone” section above for details.

Topamax dosage for children when used with other seizure drugs

The dosage of Topamax when used with other medications for seizures in children ages 2 to 16 years is based on body weight. (The dosage for children ages 17 years and older is the same as it is for adults. See the “Topamax dosage when used with other seizure drugs” section above for details.)

The starting dosage is 1 mg per kg of body weight (mg/kg) daily to 3 mg/kg daily for the first week of treatment, up to 25 mg per day. This is taken as one dose per day, in the evening.

Then, the dosage is gradually increased by 1 mg/kg per day to 3 mg/kg per day every 1 to 2 weeks. The daily dose is split into two doses, taken once in the morning and once in the evening. The dosage will be increased until the right dosage for your child is reached.

The recommended maintenance (daily) dosage is 5 mg/kg per day to 9 mg/kg per day for partial onset seizures, generalized tonic-clonic seizures, or seizures linked to Lennox-Gastaut syndrome. The daily dose is divided into two doses, given in the morning and evening.

The maximum recommended dosage is 400 mg per day.

Is Topamax used long term?

Yes, Topamax is typically used as a long-term treatment. If you and your doctor determine that Topamax is safe and effective for you, it’s likely that you’ll use it long term.

Dosage adjustments

Your doctor may need to adjust your dosage of Topamax in some cases. Factors that could affect your dosage include:

  • if you have kidney disease or other health conditions
  • if you’re taking other medications

Don’t use more Topamax than your doctor prescribes. Using more than this can lead to serious side effects.

Symptoms of overdose

Symptoms caused by an overdose can include:

What to do in case you take too much Topamax

Call your doctor right away if you think you’ve taken too much Topamax. You can also call 800-222-1222 to reach the American Association of Poison Control Centers, or you can use their online resource. But if you have severe symptoms, call 911 (or your local emergency number) immediately or go to the nearest emergency room.

Below are answers to some common questions about Topamax’s dosage.

Is Topamax used to treat bipolar disorder or depression?

Topamax doesn’t have Food and Drug Administration (FDA) approval for treating bipolar disorder or depression. But your doctor may prescribe Topamax off-label if other treatment options haven’t worked for your condition. (Off-label drug use means using a drug for a purpose other than what it’s been approved for by the FDA.)

Studies haven’t found Topamax to be highly effective when used alone or with other medications to treat bipolar disorder compared with a placebo (a treatment with no active drug).

There are limited studies on Topamax’s effectiveness for treating depression. One study found that taking Topamax with a selective serotonin reuptake inhibitor such as fluoxetine (Prozac) or citalopram (Paxil) improved symptoms in people with major depressive disorder compared with a placebo. But more studies are needed to confirm the effectiveness of Topamax for depression.

If you’re interested in taking Topamax to treat bipolar disorder or depression, talk with your doctor.

Can Topamax be prescribed to reduce alcohol cravings?

Topamax is not approved to reduce alcohol cravings. But your doctor may prescribe Topamax off-label for this use.

Although there are limited studies of Topamax for this use, one study found that Topamax may be effective for reducing alcohol cravings.

If you’re interested in using Topamax to reduce alcohol cravings, talk with your doctor to learn more.

The dosage of Topamax you’re prescribed may depend on several factors. These include:

  • the type and severity of the condition you’re using Topamax to treat
  • your age
  • your weight
  • other conditions you may have (see “Dosage adjustments” under “What is Topamax’s dosage?”)
  • if you’re taking other medications with Topamax

Topamax comes in two forms:

  • coated tablets that you swallow
  • sprinkle capsules that you can swallow whole or open and sprinkle on a small amount of soft food and swallow

You can take either form with or without food.

You shouldn’t crush, split, or chew the Topamax tablets because they have a bitter taste. If you have trouble swallowing, your doctor may prescribe the sprinkle capsules.

If you have questions about taking Topamax or about which form is right for you, talk with your doctor or pharmacist.

If you miss a dose of Topamax, you can take it when you remember as long as there are 6 hours or more until your next scheduled dose. If there are fewer than 6 hours until your next dose, just skip the missed dose and take the next dose at its regular time. You shouldn’t take two doses of Topamax together to make up for a missed dose. This can raise your risk of serious side effects.

If you need help remembering to take your dose of Topamax on time, try using a medication reminder. This can include setting an alarm or using a timer. You could also download a reminder app on your phone.

No studies have looked at whether Topamax can cause drug dependence, so it’s not known if this can occur.

But you shouldn’t suddenly stop taking Topamax. Suddenly stopping your treatment can lead to your seizures or migraine becoming more severe or occurring more often.

If you’re experiencing side effects from Topamax, talk with your doctor about your treatment options. And if you need to stop taking Topamax, your doctor may slowly decrease your dosage. This helps prevent serious side effects and worsening of your condition.

The sections above describe the typical dosages provided by the drug manufacturer. If your doctor recommends Topamax for you, they will prescribe the dosage that’s right for you.

Remember, you shouldn’t change your dosage of Topamax without your doctor’s recommendation. Only take Topamax exactly as prescribed. Talk with your doctor if you have questions or concerns about your current dosage.

Here are some examples of questions you may want to ask your doctor:

  • How often will my dosage for Topamax be adjusted if it’s not working for me?
  • Will my dosage be reduced if I have serious side effects?
  • Does my dosage of Topamax need to change if I’m taking other medications with it?

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Disclaimer: Healthline 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.