Generic Name: zonisamide (zoe NIS a mide)
Brand Name: Zonegran
What is zonisamide?
Zonisamide is a sulfa drug with anti-convulsant effects.
Zonisamide is used together with other anti-convulsant medications to treat partial seizures in adults with epilepsy.
Zonisamide may also be used for purposes not listed in this medication guide.
What is the most important information I should know about zonisamide?
Follow all directions on your medicine label and package. Tell each of your healthcare providers about all your medical conditions, allergies, and all medicines you use.
What should I discuss with my healthcare provider before taking zonisamide?
You should not use this medicine if you are allergic to zonisamide.
You may not be able to take zonisamide if you have ever had a severe allergic to a sulfa drug.
To make sure zonisamide is safe for you, tell your doctor if you have:
stomach flu or illness causing diarrhea;
a growth disorder;
a bone disorder that causes soft or weak bones or low bone mineral density;
a history of 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).
You may have thoughts about suicide while taking this medicine. Your doctor should check your progress at regular visits. Your family or other caregivers should also be alert to changes in your mood or symptoms.
In animal studies, zonisamide caused birth defects and infant death. It is not known whether these effects would occur in people taking doses recommended for humans. Ask your doctor about your personal risk. Use effective birth control to prevent pregnancy while you are taking zonisamide.
If you are already pregnant, do not start or stop taking zonisamide during pregnancy without your doctor's advice. Zonisamide can cause metabolic acidosis, which could harm an unborn baby. However, having a seizure during pregnancy could harm both the mother and the baby. Tell your doctor right away if you become pregnant while taking zonisamide.
Zonisamide can pass into breast milk and may harm a nursing baby. Tell your doctor if you are breast-feeding a baby.
Zonisamide is not approved for use by anyone younger than 18 years old.
How should I take zonisamide?
Follow all directions on your prescription label. Do not take this medicine in larger or smaller amounts or for longer than recommended.
Take zonisamide with a full glass of water. Drink 6 to 8 glasses of water each day to prevent kidney stones while you are taking zonisamide.
Zonisamide can be taken with or without food.
Swallow the zonisamide capsule whole. Do not crush, chew, open, or break it.
While using zonisamide, you may need frequent blood tests.
If you need surgery, tell the surgeon ahead of time that you are using zonisamide. You may need to stop using the medicine for a short time.
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.
If you do stop taking zonisamide for any reason, talk with your doctor before restarting the medication. You may need to restart at a lower dose.
Seizures are often treated with a combination of drugs. Use all medications as directed by your doctor. Read the medication guide or patient instructions provided with each medication. Do not change your doses or medication schedule without your doctor's advice.
Wear a medical alert tag or carry an ID card stating that you take zonisamide. Any medical care provider who treats you should know that you take seizure medication.
Store at room temperature away from moisture, heat, and light.
What happens if I miss a dose?
Take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.
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.
What should I avoid while taking zonisamide?
This medication may impair your thinking or reactions. Avoid driving or operating machinery until you know how zonisamide will affect you.
Avoid drinking alcohol. It can increase some of the side effects of zonisamide.
Zonisamide side effects
Get emergency medical help if you have signs of an allergic reaction: any form of skin rash, hives; fever, swollen glands, feeling weak or tired, severe muscle pain, unusual bruising or bleeding; yellowing of your skin or the whites of your eyes; difficult breathing; swelling of your face, lips, tongue, or throat.
Report any new or worsening symptoms to your doctor, such as: sudden mood or behavior changes, anxiety, panic attacks, trouble sleeping, or if you feel impulsive, irritable, agitated, hostile, aggressive, restless, hyperactive (mentally or physically), depressed, or have thoughts about suicide or hurting yourself.
Call your doctor at once if you have:
decreased sweating, feeling very hot;
symptoms of metabolic acidosis--loss of appetite, feeling tired, problems with thinking or talking, irregular heartbeats;
symptoms of a blood cell disorder--fever, chills, body aches, flu symptoms, sores in your mouth and throat;
symptoms of a kidney stone--severe pain in your stomach or lower back, blood in your urine;
increased or worsening seizures;
the first sign of any skin rash, no matter how mild; or
severe skin reaction--fever, sore throat, swelling in your face or tongue, burning in your eyes, skin pain followed by a red or purple skin rash that spreads (especially in the face or upper body) and causes blistering and peeling.
Common side effects may include:
problems with memory or concentration;
feeling agitated or irritable;
loss of coordination, trouble walking; or
loss of appetite.
This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
See also: Side effects (in more detail)
Zonisamide dosing information
Usual Adult Dose for Seizures:
16 years of age and older:
-Initial dose: 100 mg orally once a day
-Titration: After 2 weeks at 100 mg/day, the dose may be increased to 200 mg/day as either a single or divided dose (100 mg orally 2 times a day) for at least 2 weeks; it can then be increased to 300 mg/day, then 400 mg/day either as a single daily dose or divided into 2 daily doses, with the dose stable for at least 2 weeks to achieve steady state at each level
-Maintenance dose: 400 mg/day
-Maximum dose: 600 mg/day
-This drug may be taken with or without food.
-Capsules should be swallowed whole.
-Because of the long half-life of this drug, up to 2 weeks may be required to achieve steady state levels upon reaching a stable dose or following dosage adjustment.
-The prescriber may wish to prolong the duration of treatment at the lower doses in order to fully assess the effects of this drug at steady state (noting that many of the side effects are more frequent at doses of 300 mg per day and above). Although there is some evidence of greater response at doses above 100 to 200 mg/day, the increase appears small and formal dose response studies have not been conducted.
Use: As adjunctive therapy in the treatment of partial seizures
Usual Pediatric Dose for Seizures:
Less than 16 years of age: Not recommended
16 years of age and older: See adult dosing
What other drugs will affect zonisamide?
Taking this medicine with other drugs that make you sleepy can worsen this effect. Ask your doctor before taking zonisamide with a sleeping pill, narcotic pain medicine, muscle relaxer, or medicine for anxiety or depression.
Other drugs may interact with zonisamide, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell each of your health care providers about all medicines you use now and any medicine you start or stop using.
More about zonisamide
- Other brands: Zonegran
Related treatment guides
Where can I get more information?
- Your pharmacist can provide more information about zonisamide.
- Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.
- Disclaimer: Every effort has been made to ensure that the information provided by Cerner Multum, Inc. ('Multum') is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. Multum information has been compiled for use by healthcare practitioners and consumers in the United States and therefore Multum does not warrant that uses outside of the United States are appropriate, unless specifically indicated otherwise. Multum's drug information does not endorse drugs, diagnose patients or recommend therapy. Multum's drug information is an informational resource designed to assist licensed healthcare practitioners in caring for their patients and/or to serve consumers viewing this service as a supplement to, and not a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners. The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug or drug combination is safe, effective or appropriate for any given patient. Multum does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse or pharmacist.
Copyright 1996-2012 Cerner Multum, Inc. Version: 10.04.
Date modified: January 10, 2017
Last reviewed: May 02, 2016