Zonisamide

This information from Lexicomp® explains what you need to know about this medication, including what it’s used for, how to take it, its side effects, and when to call your healthcare provider.

Brand Names: US

Zonegran; Zonisade

What is this drug used for?

  • It is used to treat seizures.
  • It may be given to you for other reasons. Talk with the doctor.

What do I need to tell my doctor BEFORE I take this drug?

  • If you are allergic to this drug; any part of this drug; or any other drugs, foods, or substances. Tell your doctor about the allergy and what signs you had.
  • If you have a sulfa allergy.
  • If you have kidney disease.

This is not a list of all drugs or health problems that interact with this drug.

Tell your doctor and pharmacist about all of your drugs (prescription or OTC, natural products, vitamins) and health problems. You must check to make sure that it is safe for you to take this drug with all of your drugs and health problems. Do not start, stop, or change the dose of any drug without checking with your doctor.

What are some things I need to know or do while I take this drug?

  • Tell all of your health care providers that you take this drug. This includes your doctors, nurses, pharmacists, and dentists.
  • If you are allergic to tartrazine (FD&C Yellow No. 5), talk with your doctor. Some products have tartrazine.
  • Avoid driving and doing other tasks or actions that call for you to be alert until you see how this drug affects you.
  • Sweating less has happened with this drug mainly in children. Sometimes, this has led to heat stroke and hospital stays. Talk with the doctor.
  • Be careful in hot weather or while being active. Drink lots of fluids to stop fluid loss.
  • If seizures are different or worse after starting this drug, talk with the doctor.
  • This drug may cause an acid blood problem (metabolic acidosis). The chance may be higher in children and in people with kidney problems, breathing problems, or diarrhea. The chance may also be higher if you take certain other drugs, if you have surgery, or if you are on a ketogenic diet. Over time, metabolic acidosis can cause kidney stones, bone problems, or growth problems in children.
  • Like other drugs that may be used for seizures, this drug may rarely raise the risk of suicidal thoughts or actions. The risk may be higher in people who have had suicidal thoughts or actions in the past. Call the doctor right away about any new or worse signs like depression; feeling nervous, restless, or grouchy; panic attacks; or other changes in mood or behavior. Call the doctor right away if any suicidal thoughts or actions occur.
  • Rarely, severe effects have happened with sulfa drugs. Sometimes, these have been deadly. These effects have included liver problems, blood problems, and severe skin reactions (Stevens-Johnson syndrome/toxic epidermal necrolysis). Call your doctor right away if you have a rash; red, swollen, blistered, or peeling skin; red or irritated eyes; sores in your mouth, throat, nose, or eyes; fever, chills, or sore throat; cough that is new or worse; feeling very tired or weak; any bruising or bleeding; or signs of liver problems like dark urine, tiredness, decreased appetite, upset stomach or stomach pain, light-colored stools, throwing up, or yellow skin or eyes.
  • This drug may affect growth in children and teens in some cases. They may need regular growth checks. Talk with the doctor.
  • This drug is not approved for use in children younger than 16 years of age. Talk with the doctor.
  • This drug may cause harm to the unborn baby if you take it while you are pregnant.
  • If you may become pregnant, you must use birth control while taking this drug and for some time after the last dose. Ask your doctor how long to use birth control. If you get pregnant, call your doctor right away.
  • If you used this drug when you were pregnant, tell your baby’s doctor.
  • Tell your doctor if you are breast-feeding. You will need to talk about any risks to your baby.

What are some side effects that I need to call my doctor about right away?

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:

  • Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
  • Signs of too much acid in the blood (acidosis) like confusion; fast breathing; fast heartbeat; a heartbeat that does not feel normal; very bad stomach pain, upset stomach, or throwing up; feeling very sleepy; shortness of breath; or feeling very tired or weak.
  • Signs of high ammonia levels like a heartbeat that does not feel normal, breathing that is not normal, feeling confused, pale skin, slow heartbeat, seizures, sweating, throwing up, or twitching.
  • Change in balance.
  • Not sweating during activities or in warm temperatures.
  • High fever, fever that goes away and comes back, or long-lasting fever.
  • Back pain, belly pain, or blood in the urine. May be signs of a kidney stone.
  • Not able to focus.
  • Trouble speaking.
  • Memory problems or loss.
  • Hallucinations (seeing or hearing things that are not there).
  • Bone pain.
  • Very bad muscle pain or weakness.
  • This drug may cause very bad eye problems. If left untreated, this can lead to lasting eyesight loss. Call your doctor right away if you have new eye signs like blurred eyesight or other changes in eyesight, eye pain, or eye redness.
  • A severe and sometimes deadly effect has happened in people taking drugs for seizures like this drug. Call your doctor right away if you have swollen glands; fever; rash; painful sores in the mouth or around the eyes; chest pain; signs of kidney problems like unable to pass urine or change in the amount of urine passed; or signs of liver problems like dark urine, tiredness, decreased appetite, upset stomach or stomach pain, light-colored stools, throwing up, or yellow skin or eyes.

What are some other side effects of this drug?

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

  • Feeling dizzy, sleepy, tired, or weak.
  • Headache.
  • Upset stomach.
  • Decreased appetite.
  • Stomach pain or diarrhea.
  • Trouble sleeping.

These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.

You may report side effects to your national health agency.

You may report side effects to the FDA at 1-800-332-1088. You may also report side effects at https://www.fda.gov/medwatch.

How is this drug best taken?

Use this drug as ordered by your doctor. Read all information given to you. Follow all instructions closely.

All products:

  • Take with or without food.
  • Drink lots of noncaffeine liquids unless told to drink less liquid by your doctor.
  • Keep taking this drug as you have been told by your doctor or other health care provider, even if you feel well.
  • Do not stop taking this drug all of a sudden without calling your doctor. You may have a greater risk of seizures. If you need to stop this drug, you will want to slowly stop it as ordered by your doctor.
  • Talk with your doctor before you use alcohol, marijuana or other forms of cannabis, or prescription or OTC drugs that may slow your actions.
  • Have blood work checked as you have been told by the doctor. Talk with the doctor.

Capsules:

  • Swallow whole. Do not chew, open, or crush.

Liquid (suspension):

  • Shake well before use.
  • Measure liquid doses carefully. Use the measuring device that comes with this drug. If there is none, ask the pharmacist for a device to measure this drug.
  • Do not use a household teaspoon or tablespoon to measure this drug. Doing so could lead to the dose being too high.

What do I do if I miss a dose?

  • Take a missed dose as soon as you think about it.
  • If it is close to the time for your next dose, skip the missed dose and go back to your normal time.
  • Do not take 2 doses at the same time or extra doses.

How do I store and/or throw out this drug?

All products:

  • Store at room temperature protected from light. Store in a dry place. Do not store in a bathroom.
  • Keep all drugs in a safe place. Keep all drugs out of the reach of children and pets.
  • Throw away unused or expired drugs. Do not flush down a toilet or pour down a drain unless you are told to do so. Check with your pharmacist if you have questions about the best way to throw out drugs. There may be drug take-back programs in your area.

Liquid (suspension):

  • After opening, throw away any part not used after 30 days.

General drug facts

  • If your symptoms or health problems do not get better or if they become worse, call your doctor.
  • Do not share your drugs with others and do not take anyone else’s drugs.
  • Some drugs may have another patient information leaflet. If you have any questions about this drug, please talk with your doctor, nurse, pharmacist, or other health care provider.
  • This drug comes with an extra patient fact sheet called a Medication Guide. Read it with care. Read it again each time this drug is refilled. If you have any questions about this drug, please talk with the doctor, pharmacist, or other health care provider.
  • If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.

Consumer Information Use and Disclaimer

This generalized information is a limited summary of diagnosis, treatment, and/or medication information. It is not meant to be comprehensive and should be used as a tool to help the user understand and/or assess potential diagnostic and treatment options. It does NOT include all information about conditions, treatments, medications, side effects, or risks that may apply to a specific patient. It is not intended to be medical advice or a substitute for the medical advice, diagnosis, or treatment of a health care provider based on the health care provider’s examination and assessment of a patient’s specific and unique circumstances. Patients must speak with a health care provider for complete information about their health, medical questions, and treatment options, including any risks or benefits regarding use of medications. This information does not endorse any treatments or medications as safe, effective, or approved for treating a specific patient. UpToDate, Inc. and its affiliates disclaim any warranty or liability relating to this information or the use thereof. The use of this information is governed by the Terms of Use, available at https://www.wolterskluwer.com/en/know/clinical-effectiveness-terms.

Last Reviewed Date

2022-10-12

Copyright

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Last Updated

Monday, December 12, 2022