NZ Formulary



What does it do?

Topiramate is used to treat and prevent seizures. Sometimes it is used for other conditions, such as preventing migraines.

Before you start

  • Tell your doctor if you have kidney problems or angle-closure glaucoma.
  • Tell your doctor if you are pregnant, planning to become pregnant, or breastfeeding.

How should you take it?

Take topiramate regularly as directed with a glass of water. You can take it with or without food.
Capsule: If you have trouble swallowing you can open the capsule and sprinkle the contents on a small amount of soft food. Swallow the mixture straight away.

What if you forget a dose?

Take the missed dose as soon as possible and continue as directed.

Can you take other medicines?

Some medicines available without a prescription may react with topiramate including:

  • some antihistamines, such as chlorphenamine, hyoscine, meclozine and promethazine. These can be in medicines for allergies, nausea and colds.

Tell your pharmacist or doctor about all medicines or treatments that you may be taking, including vitamins, herbal products (e.g. ginkgo) or recreational drugs (e.g. ecstasy).

Important information continues on next page.

What side effects might you notice?

Side EffectsRecommended action

Suicidal thoughts

Blurred vision, eye pain

Tell your doctor immediately

Confusion, loss of co-ordination/walking or handwriting problems, memory problems, trouble concentrating

Mood changes, nervousness

Tingling or numbness, tremor

Lower back pain, pink/red/brown pee (may be a kidney stone)

Tell your doctor

Dizziness, drowsiness, slow or slurred speech


Tiredness or weakness

Dry mouth or throat, changes in taste, loss of appetite, weight loss

Stomach upset

Tell your doctor if troublesome

If you notice any other effects, discuss them with your doctor or pharmacist.

Other information:

  • Some special diets (e.g. ketogenic) may react with topiramate – talk to your doctor.
  • Topiramate can impair your ability to do tasks such as driving or using machines. Alcohol makes this worse. Discuss your risk with your health professional. (search NZTA - Are you safe to drive?)
  • Topiramate may cause kidney stones. Drinking plenty of water can help to prevent this.
  • Do not stop taking topiramate without talking to your doctor first.