In the U.S.—

In Canada—

• Anticonvulsant
• Anti-migraine headache

Topiramate (toe-PYRE-a-mate) is used to help control some types of seizures in the treatment of epilepsy. This medicine cannot cure epilepsy and will only work to help control seizures for as long as you continue to take it.

This medicine is available only with your doctor's prescription, in the following dosage form:

Oral
• Tablets (U.S. and Canada)
• Capsules (U.S and Canada.)

In deciding to use a medicine, the risks of taking topiramate must be weighed against the good it will do. This is a decision you and your doctor will make. For topiramate, the following should be considered:

Allergies—Tell your doctor if you have ever had any unusual or allergic reaction to topiramate. Also tell your health care professional if you are allergic to any other substances, such as foods, preservatives, or dyes.

Pregnancy—Topiramate has not been studied in pregnant women. However, studies in pregnant animals have shown that topiramate may cause birth defects in the offspring, as well as adverse effects in the mother, when given in doses many times higher than the human dose. Before taking this medicine, make sure your doctor knows if you are pregnant or if you may become pregnant.

Breast-feeding—It is not known whether topiramate passes into breast milk. Although most medicines pass into breast milk in small amounts, many of them may be used safely while breast-feeding. Mothers who are taking this medicine and who wish to breast-feed should discuss this with their doctor.

Children—Although there is no specific information comparing the use of topiramate in children with use in other age groups, this medicine is not expected to cause different side effects or problems in children than it does in adults.

Older adults—In studies done to date that have included adults older than 60 years of age, topiramate has not been shown to cause different side effects or problems in older people than it does in younger adults.

Other medicines—Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking topiramate, it is especially important that your health care professional know if you are taking any of the following:

• Acetazolamide (e.g., Diamox) or
• Dichlorphenamide (e.g., Daranide)—Taking these medicines with topiramate may increase the chance of getting kidney stones
• Carbamazepine (e.g., Tegretol)—Blood levels of topiramate may be decreased. Your doctor may need to adjust the dosage of either or both medicines
• Oral contraceptives (birth control pills) containing estrogen—Topiramate may decrease the effects of these medicines; contraceptive failure may result; additional birth control measures may be needed to decrease the risk of pregnancy
• Phenytoin (e.g., Dilantin)—Blood levels of topiramate may be decreased. Your doctor may need to adjust the dosage of either or both medicines
• Valproic acid (e.g., Depakene, Depakote)—Blood levels of topiramate and/or valproic acid may be decreased. Your doctor may need to adjust the dosage of either or both medicines

• History of kidney stones—Risk of having kidney stones again may be increased

• Kidney problems or
• Liver problems—Higher blood levels of topiramate may result and increase the chance of side effects

Take this medicine every day exactly as ordered by your doctor in order to improve your condition as much as possible. Do not take more or less of it, and do not take it more or less often than your doctor ordered.

Topiramate may be taken with or without food, on a full or an empty stomach. Swallow the tablets whole, without breaking, crushing, or chewing them. The bitter taste may be more noticeable if the tablets are held in the mouth or chewed. The capsules may be swallowed whole, or the contents of the capsule may be opened and the contents sprinkled on a small amount (teaspoonful) of soft food (such as applesauce, custard, ice cream, oatmeal, pudding, or yogurt) and swallowed immediately without chewing

Dosing—

The dose of topiramate will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of topiramate. If your dose is different, do not change it unless your doctor tells you to do so.

The number of tablets that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are taking topiramate.

• For oral dosage form (tablets or capsules):
  • As an anticonvulsant:
    • Adults—At first, 50 milligrams (mg) a day for the first week. Your doctor may increase your dose gradually every week if needed and tolerated, but the usual dose is not greater than 400 mg a day.
    • Children (age 2 to 16 years)—At first, 25 milligrams (mg) nightly for the first week. Your doctor may increase your dose gradually every 1 or 2 weeks to be taken in two divided doses.

Missed dose—

If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

Storage—

To store this medicine:

• Keep out of the reach of children.
• Store away from heat and direct light.
• Do not store in the bathroom, near the kitchen sink, or in other damp places. Heat or moisture may cause the medicine to break down.
• Keep the medicine from freezing. Do not refrigerate.
• Do not keep outdated medicine or medicine no longer needed. Be sure that any discarded medicine is out of the reach of children.

This medicine may cause some people to have blurred vision, double vision, clumsiness or unsteadiness, or to become dizzy, drowsy, or have trouble in thinking. Make sure you know how you react to this medicine before you drive, use machines, or do anything else that could be dangerous if you are not alert, well-coordinated, or able to think or see well.

Check with your doctor immediately if you experience a decrease in vision, blurred vision, double vision or pain around the eyes.

Oral contraceptives (birth control pills) containing estrogen may not work properly if you take them while you are taking topiramate. Unplanned pregnancies may occur. You should use a different or additional means of birth control while you are using topiramate. If you have any questions about this, check with your doctor or pharmacist.

It is important that you drink plenty of fluids every day during therapy with topiramate to help prevent kidney stones from forming.

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

• More common
  • Any vision problems, especially blurred vision, double vision, eye pain or rapidly decreasing vision;  burning, prickling, or tingling sensations;  clumsiness or unsteadiness ;  confusion;  continuous, uncontrolled back-and-forth or rolling eye movements;  dizziness;  drowsiness;  eye redness;  generalized slowing of mental and physical activity;  increased eye pressure;  memory problems;  menstrual changes;  menstrual pain;  nervousness;  speech or language problems;  trouble in concentrating or paying attention;  unusual tiredness or weakness 
  
  

• Less common
  • Abdominal pain;  fever, chills, or sore throat;  lessening of sensations or perception;  loss of appetite;  mood or mental changes, including aggression, agitation, apathy, irritability, and mental depression ;  red, irritated, or bleeding gums;  weight loss 
  
  

• Rare
  • Blood in urine;  decrease in sexual performance or desire;  difficult or painful urination;  eye pain;  frequent urination;  hearing loss;  itching;  loss of bladder control;  lower back or side pain;  nosebleeds;  pale skin;  red or irritated eyes;  ringing or buzzing in ears;  skin rash;  swelling;  troubled breathing 
  
  

Other side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. However, check with your doctor if any of the following side effects continue or are bothersome:

• More common
  • Breast pain in women;  nausea;  tremors 
  
  

• Less common
  • Back pain;  chest pain;  constipation;  heartburn;  hot flushes;  increased sweating;  leg pain 
  
  

Topiramate may cause a change in your sense of taste.

Other side effects not listed above may also occur in some patients. If you notice any other effects, check with your doctor.

• Incidence not determined--—Observed during clinical practice; estimates of frequency cannot be determined
  • abdominal or stomach pain;  bloating;  clay-colored stools;  confusion;  constipation;  fatigue;  fever;  increased rate of breathing;  yellow eyes or skin;  muscle pain 
  
  

Once a medicine has been approved for marketing for a certain use, experience may show that it is also useful for other medical problems. Although these uses are not included in the product labeling, topiramate is used in certain patients with the following medical conditions:

• Migraine headaches