Topamax is not available in generic (non-brand) form in the United States. There is also an extended release formulation targeted for mid-2013.

Topamax is marketed in the United States by Ortho-McNeil Pharmaceuticals. The name or appearance may differ in other countries. The dose (measured in milligrams, abbreviated "mg") will usually be the same. These descriptions apply to the U.S. versions:

Topamax (TOH-pah-maks) is the brand name used in the United States, Canada, the United Kingdom, Australia, and some other countries for the seizure medicine topiramate (toh-PEER-ah-mate).


Updated: 17/10/2023

Brand Name(s)


Used to Treat

Lennox-Gastaut Syndrome
Focal Impaired Awareness or Complex Partial Seizures
Focal Aware Onset Seizure
Tonic-clonic Seizures



25 mg (round, cream)
Tablets marked "25" on one side and "OMN" on the other.

Topamax 50mg

50 mg (round, light-yellow)
Tablets marked "50" on one side and "OMN" on the other.

Topamax 100mg

100 mg (round, yellow)
Tablets marked "100" on one side and "OMN" on the other

Topamax 200mg

200 mg (round, salmon)
Tablets marked "200" on one side and "OMN" on the other.

Topamax 15mg

15 mg (white, clear)
Gelatin capsules containing small white to off-white beads, marked "TOP" and "15 mg" on side.

Topamax 25mg

25 mg (not shown) (white, clear)
Gelatin capsules containing small white to off-white beads, marked "TOP" and "25 mg" on side"

Package Insert

Frequently Asked Questions

    How to take and store Topiramate?

    Follow your doctor's directions. Call if you have any questions. Usually, your doctor will tell you to start by taking one 25-milligram tablet two times each day. After a while, the doctor may gradually increase the dosage to get better control of your seizures. Because topiramate is generally taken two times a day, many people help themselves to remember by taking it with breakfast and dinner. Ask the doctor what to do if you forget to take a dose.

    Both forms of Topamax can be taken either with food or without food, but it's best to be consistent from day to day.

    Be careful if the doctor writes a new prescription using a different kind of pill. For example, if you've been using 25-mg tablets and the new prescription is for 100-mg tablets, be careful to use the correct number. Don't automatically continue to use the same number of pills as before. Make sure you know what size tablet has been prescribed.

    If you take tablets, swallow each one whole. Don't bite it. (It will be quite bitter.)

    Sprinkle capsules are an easy way to give Topamax to children and others who have trouble swallowing pills. The capsules can be swallowed whole, but usually they are opened and the contents are sprinkled onto a teaspoon of soft food such as applesauce, custard, ice cream, oatmeal, pudding, or yogurt. Here's the procedure:

    • Get the teaspoon of food ready.
    • Hold the capsule upright so you can read the word "TOP."
    • Hold the capsule over the food and twist off the clear portion of the capsule.
    • Sprinkle all of the capsule's contents onto the food.
    • Swallow the entire spoonful right away without chewing it. (It will taste bitter if it's chewed.) Drinking some water or another fluid right away can help make sure that all the food is swallowed. Never save any medicine that has been mixed with food to use later.

    Be sure to take only the amount that your doctor tells you to take. If you think you've taken one or two extra tablets or capsules, call your doctor for advice. For a larger overdose, call your local poison control center or emergency room right away.

    Don't take more than the doctor prescribes. Be sure to use only the amount of Topamax that your doctor prescribes. If you think you've taken one or two extra tablets, call your doctor for advice. For a larger overdose, call your local poison control center or emergency room right away, unless you have special directions from the doctor.

    Don't stop taking Topamax or change the amount you take without talking to your doctor first. Stopping any seizure medicine all at once can cause serious problems.

    Both the tablets and capsules should be stored at room temperature (59° to 86°F or 15° to 30°C), in a tightly sealed container protected from moisture and humidity. Be especially careful to protect the sprinkle capsules from heat and store below 77°F (25°C). If you pick up the prescription in warm weather, don't leave them in the car while you run other errands!

    What if I forget?

    If you forget a dose, take it as soon as you remember. If it is almost time for the next dose, delay that dose for a few hours instead of taking two doses very close together. Talk to your doctor for specific instructions on how to make it up. Do not double up or take extra medicine, unless instructed to do so by your doctor.

    Do your best to follow the doctor's directions. If you forget doses often, it may be a good idea to get a special pillbox or watch with an alarm to remind you.

    Taking the right amount of seizure medicine on time every single day is the most important step in preventing seizures!

    How does Topiramate affect the brain?

    Brain cells need to work (fire) at a certain rate to function normally. During a seizure, brain cells are forced to work much more rapidly than normal. Topamax helps prevent brain cells from working as fast as a seizure requires them to. In this way, seizures can be stopped when they are just beginning.

    How does the body digest Topiramate?

    After medicine is swallowed, it must be absorbed into the blood so it can move throughout the body. The process of absorbing, digesting, and excreting a medicine or food is called metabolism. The way the body metabolizes a particular medicine affects how often it must be taken. It also determines whether it will interact with other medicines or be affected by liver disease or kidney disease.

    Like many other medicines, Topamax is broken down (digested) in the liver. People with liver disease must be cautious about taking it. Other people also need to be careful if they take other medicines that are digested in the liver. The metabolism of each medicine may be affected, changing how quickly it works and leaves the body.

    Topamax is eliminated from the body through the kidneys.

    How well does the Topiramate work?

    Doctors have studied large numbers of people with partial seizures, generalized tonic-clonic (grand mal) seizures, or seizures from Lennox-Gastaut syndrome to find out how well Topamax works.

    Studies have shown that Topamax works well alone(monotherapy)and when added to other seizure medicines. Topamax is not a perfect add-on seizure medicine for everyone, however. Sometimes people must try a series of combinations before finding what is best for them. Some other medicines affect how Topamax is eliminated from the body, so the dosages may need to be changed with different combinations.

    What are the most common side effects of Topiramate?

    Most people who take Topamax (topiramate) have little or no problem with side effects. Those with problems most often complain of:

    • fatigue or drowsiness
    • difficulty with concentration
    • difficulty finding the right word (word retrieval)
    • confusion
    • dizziness
    • unsteadiness
    • a feeling of pins and needles, usually in the tips of the fingers and toes
    • loss of appetite and weight loss
    • nervousness
    • depression
    • difficulty with memory

    Most of these problems are more common when higher doses of Topamax are taken.

    A few people do experience psychiatric disorders when they take Topamax.

    If you notice any of these problems, call the doctor's office. Sometimes the doctor can help by changing the amount of Topamax you take or how you take it. Don't stop taking Topamax or change the amount you take without the doctor's guidance.

    The most common side effects with Topamax are fatigue and sleepiness. If you've just started taking Topamax or have just had your dosage increased, be careful about doing things that could be dangerous (like driving or operating machinery) until you know how it will affect you. Be especially cautious if you tend to be sensitive to medications.

    Be sure to read about the serious side effects so you will be aware of a few serious problems that could arise when you take Topamax. These serious problems are very rare but everyone who takes this medicine should at least be aware of them.

    You shouldn't stop taking Topamax or any other seizure medicine without your doctor's advice.

    Allergic reactions
    A small percentage of people who take Topamax develop a skin rash within the first few weeks of taking it. If this happens, tell the doctor or nurse right away, to be sure that it's not the beginning of a serious problem. It's rare for the rash to be serious, but don't ignore it. It's often necessary to switch to a different seizure medicine.

    What are the most serious side effects of Topiramate?

    Very few people have serious reactions to Topamax. If you take it, you should be aware of them, however, so you and your family can recognize them.

    A very small number of people treated with Topamax developed an eye condition like glaucoma. If you experience blurred vision or difficulty seeing that comes on quickly, perhaps with eye pain, notify your doctor immediately. These symptoms usually occurred during the first month of treatment. If action is taken promptly (including stopping the Topamax), the symptoms will go away, but if they are not treated, permanent loss of vision could result.

    Kidney stones
    About 1 in 50 adults taking Topamax have developed kidney stones. They are more common in men and in those who have had them before. They also may be more likely to occur if Diamox (acetazolamide) or Zonegran (zonisamide) is also taken or if the ketogenic diet (a special diet sometimes used to control seizures in children) is followed. Topamax therefore should be used cautiously in people taking Diamox or Zonegran or using the ketogenic diet.

    To help prevent kidney stones, drink plenty of water, juice, or other fluids (8 glasses every day for adults). Sharp pains in your side or lower back may signal the onset of a kidney stone. Consult a doctor immediately or go to the emergency room.

    One factor that may increase the risk of kidney stones, fatigue, and other disorders is abnormally acid blood, called metabolic acidosis. Symptoms of metabolic acidosis may include tiredness, loss of appetite, irregular heartbeat, and impaired consciousness. Call your health care professional right away if these symptoms develop while taking Topamax.

    This effect has been found to some extent in up to two-thirds of children taking Topamax and about one-third of adults. Much smaller numbers show very abnormal results on blood tests.

    The doctor will probably test the blood before starting treatment with Topamax and again from time to time while Topamax is being used, to check for acidosis. If the results are abnormal, the doctor may recommend stopping Topamax or starting treatment for acidosis to prevent any serious effects.

    Inadequate sweating
    Some children who take Topamax may not sweat enough in hot weather, causing their body temperatures to rise, sometimes to dangerous levels. Children should be monitored in hot weather to be sure they sweat appropriately.

    Bone Health
    While the effect of Topamax on bone health is not fully known, a person who develops metabolic acidosis can develop thinning of the bones and bone loss if the condition is not treated properly. Regular exercise and diet are very important to help keep strong bones. People should talk to their doctor before taking calcium supplements however, because extra calcium could increase the risk of kidney stones in some people who are also taking topiramate. People who have thinning of the bones may also need to take prescription medicines to treat this. Talk to your doctor about tests to check your bone health and what to do next.

    A complete list of all reactions to Topamax can be found in the package insert. It is important to remember that only a tiny number of people who take Topamax have any of these serious problems.

    If you believe that you have experienced a serious side effect from a medication, you or your physician can bring it to the attention of the FDA, through their MedWatch program, by completing an adverse event report form ( MedWatch is the FDA's program for reporting serious reactions and problems with medical products, such as drugs and medical devices. ( To learn more about the Medwatch program go to:

    On July 10, 2008, an advisory panel was convened by the Food and Drug Administration (FDA) to review data that the FDA had previously collected from drug studies showing an association between many of the antiepileptic drugs (AEDs) and suicidal ideation and behavior, which together are called suicidality. According to the FDA’s Alert, among the patients with epilepsy in these drug studies, 1 out of 1000 people taking the placebo (inactive substance) showed suicidality compared to approximately 3.5 out of 1000 people who took an AED. The FDA advisory panel voted to accept the FDA's data at its meeting on July 10.

    • Taking antiepileptic medicines may increase the risk of having suicidal thoughts or actions;
    • Do not make any changes to the medication regimen without first talking with the responsible healthcare professional;
    • Pay close attention to any day-to-day changes in mood, behavior and actions. These changes can happen very quickly so it is important to be mindful of any sudden differences.
    • Be aware of common warning signs that might be a signal for risk of suicide. Some of these are:
      • Talking or thinking about wanting to hurt yourself or end your life
      • Withdrawing from friends and family
      • Becoming depressed or having your depression get worse
      • Becoming preoccupied with death and dying
      • Giving away prized possessions

    We again urge patients and families to contact their doctor before stopping an epilepsy medication because this may possibly lead to seizures and worsening of mood.

    What else is Topiramate used for?

    Often doctors find that medicines are useful for more than one purpose. It is legal to prescribe medicines for ""off-label uses"" even though the FDA has not formally approved such use. Common off-label uses of Topamax include:

    • a type of seizure called infantile spasms (West syndrome)
    • a type of seizure called myoclonic seizures
    • the prevention of migraine headaches
    • weight loss
    • painful nerve conditions
    Who should not take Topiramate?

    The only people who definitely should not take Topamax are those who are allergic to it. People with a history of kidney stones or those who need to take high doses of vitamin C or calcium supplements, however, also probably should not take Topamax because of the increased risk of kidney stones.

    People who have kidney disease need to be extra cautious about taking Topamax.

    Can Topiramate be taken with other medicines?

    Sometimes one kind of medicine changes the way another kind of medicine works in the body. If two kinds of medicine affect each other, the doctor may prescribe something else or change the amount to be taken.

    Topamax makes birth control pills less effective, so the chances of becoming pregnant are greater. Women who use pills for birth control should talk to the doctor who prescribed them right away if they start taking Topamax. The same is true for some other forms of birth control such as Depo-Provera or implants. Topamax does not affect barrier types of birth control, like condoms, IUDs, and diaphragms.

    Topamax also affects the way the body handles phenytoin (Dilantin, Phenytek), so if you take phenytoin, ask your doctor whether you should change your dose of phenytoin.

    How do other medicines affect Topamax?
    Your body gets rid of Topamax quicker if you are also taking certain seizure medicines, such as:

    • carbamazepine (Tegretol, Tegretol XR, Carbatrol)
    • phenytoin (Dilantin, Phenytek)
    • phenobarbital
    • primidone (Mysoline)

    If this applies to you, your doctor may plan to give you more Topamax than you would otherwise take.

    Any time one of your doctors suggests starting or stopping a prescription, be sure to ask what effect it might have on the Topamax, and whether the dosage should be increased or decreased.

    What are the effects of Topiramate on Children?

    Topamax is used in addition to other seizure medicines to treat children with partial seizures, children with Lennox-Gastaut syndrome, and children with primary generalized tonic-clonic seizures.

    Doctors figure out how much medicine to give to young children based mostly on their weight. To keep side effects at a minimum, the doctor probably will prescribe a low dose to start with and increase it slowly. Children usually start with a dose of 15 to 25 milligrams (mg) or less per day, based on a range of 1 to 3 mg per kilogram (kg, about 2.2 pounds) of body weight per day. This dose is given every night for the first week. The dose is usually then increased every week or two by adding 1 to 3 mg per kg per day (given in two divided doses) to achieve the best response. Most children do best at about 5 to 9 mg per kg per day.

    If the dosage is increased slowly and carefully monitored, side effects should not be a problem for most children. The most common side effects involve problems with thinking or behavior, such as difficulty with concentration and attention or memory difficulty. These side effects may be less frequent in children than in adults. Headache, sleepiness, fatigue, and weight loss are other common side effects. Children are also less like to get the rare eye problem (glaucoma) – still, call the doctor immediately if the child experiences vision problems or eye pain.

    One advantage of using Topamax for children is that it comes in the form of a sprinkle capsule, which can be swallowed whole or given by carefully opening the capsule and sprinkling the entire contents on a small amount (teaspoon) of soft food. This mixture should be swallowed immediately and not chewed. See "How to take and store Topamax" for details.

    Children should be monitored in hot weather to be sure they sweat appropriately. Topamax impairs sweating in a few children, leading to high body temperatures.

    If a woman takes Topiramate during pregnancy will it hurt the baby?

    In the United States, the Food and Drug Administration (FDA) assigns each medication to a Pregnancy Category according to whether it has been proven to be harmful in pregnancy. Topamax is listed in Pregnancy Category C. This indicates that caution is advised, but the benefits of the medicine may outweigh the potential risks. Studies in animals have shown some harm to the baby, but there haven't been any good studies of results in women.

    Talk to your doctor or another health professional if you are pregnant or plan to become pregnant. We don't yet have enough information to be able to estimate the risk of various types of birth defects that might occur if Topamax is taken during pregnancy. We also don't know enough to compare the risk with Topamax to the risk with other seizure medicines. The risk of birth defects is generally higher for women who take more than one seizure medication and for women with a family history of birth defects.

    Women who are capable of becoming pregnant should take at least 400 mcg (0.4 mg) of folic acid (folate) daily to help prevent a type of birth defect called a neural tube defect. (The best-known of these is spina bifida, in which the spinal cord is not completely enclosed.) Women at high risk, such as those who have already had a baby with this kind of defect, should take 4000 mcg (4 mg) daily, beginning before they become pregnant.

    There is limited information on how much Topamax is passed through breast milk. The potential for serious side effects in nursing infants is unknown. If you want to breastfeed your baby, check with your doctor about what seizure medicine would be best for you.

    What are the effects of Topiramate on Seniors

    Topamax is often prescribed for people over 65 with epilepsy. Seniors have poorer kidney function than young adults, however, and Topamax is eliminated from the body by the kidneys. So dosages of Topamax for seniors should be smaller, to keep the medication from building up in the body.

    Seniors also may be more sensitive to the side effects of Topamax, such as problems with their thinking.

    What are the dose ranges for Topiramate?

    The best amount is the amount that completely controls seizures without causing troublesome side effects. It depends on many factors, which are different for every individual. Follow the doctor's directions. Call if you have any questions.

    In young adults, Topamax is usually started at 25-50 milligrams (mg) per day. Every 7 to 10 days, the amount can be increased by 50-100 mg per day as required (if side effects are not troublesome) to a target dose of 200 to 400 mg per day, divided into 2 doses.

    People over age 65 generally require a lower initial dose and particular caution with any increases.

    Read the package insert of Topiramate

    In the United States, companies that manufacture medicines are required to publish certain kinds of information about each product. This document is commonly known as a “package insert” because it is usually included with each package of the medicine.

    You can also read these documents (also called "prescribing information") online. The U.S. package insert for Topamax (topiramate) is found at:

    Some of the information may differ in other countries.

    To learn how to read and understand a package insert, see  "How to read a package insert."


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