Taking zonisamide can cause permanent vision loss. Tell your doctor right away if you have any eye pain or redness or any changes in your vision.
Some people have thoughts about suicide while taking zonisamide. Stay alert to changes in your mood or symptoms. Report any new or worsening symptoms to your doctor.
Before taking this medicine
You should not use zonisamide if you are allergic to it.
You may not be able to take zonisamide if you have ever had a severe allergic to a sulfa drug.
Tell your doctor if you have ever had:
liver disease;
kidney disease;
high levels of ammonia;
stomach flu or illness causing diarrhea;
a growth disorder;
a bone disorder that causes soft or weak bones or low bone mineral density;
depression, or suicidal thoughts or actions;
if you have ever had metabolic acidosis (too much acid in your blood); or
if you have been on a ketogenic diet (high-fat, high-protein, low-carb).
Some people have thoughts about suicide while taking zonisamide. Your doctor will need to check your progress at regular visits. Your family or other caregivers should also be alert to changes in your mood or symptoms.
Zonisamide may harm an unborn baby. Use effective birth control to prevent pregnancy, and tell your doctor if you become pregnant.
If you are pregnant, your name may be listed on a pregnancy registry to track the effects of zonisamide on the baby.
You should not breastfeed while using zonisamide.
Zonisamide is not approved for use by anyone younger than 16 years old.
How should I take zonisamide?
Follow all directions on your prescription label and read all medication guides or instruction sheets. Your doctor may occasionally change your dose. Use the medicine exactly as directed.
Zonisamide can be taken with or without food.
Swallow the capsule whole and do not crush, chew, break, or open it.
While using zonisamide, you may need frequent blood tests.
Do not stop using zonisamide suddenly, even if you feel fine. Stopping suddenly may cause increased seizures. Follow your doctor's instructions about tapering your dose.
Do not share  zonisamide with another person, even if they have the same symptoms you have.
Store at room temperature away from moisture, heat, and light.
What happens if I miss a dose?
Take the medicine as soon as you can, but skip the missed dose if it is almost time for your next dose. Do not take two doses at one time.
What happens if I overdose?
Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.
Overdose symptoms may include slow heart rate, feeling light-headed, fainting, and slow or shallow breathing.
