Patient info Open main menu

Zonisamide Teva 100 mg capsules hard – patient leaflet, side effects, dosage

Last updated: · Text from the MHRA, as of · About this document

Medicine status: Prescription only (POM) Details

Medicine strength:
100 mg
Contains active substance:
ATC code:

Patient leaflet - Zonisamide Teva 100 mg capsules hard

What Zonisamide Teva is and what it is used for

Zonisamide Teva contains the active substance zonisamide, and is used as an anti-epileptic medicine.

Zonisamide Teva is used to treat seizures that affect one part of the brain (partial seizure), which may or may not be followed by a seizure affecting all of the brain (secondary generalisation).

Zonisamide Teva may be used:

  • on its own to treat seizures in adults
  • with other anti-epileptic medicines to treat seizures in adults, adolescents, and children aged 6 years and above.

2

What you need to know before you take Zonisamide Teva

Do not take Zonisamide Teva:

  • if you are allergic to zonisamide or any of the other ingredients of this medicine (listed in section 6)
  • if you are allergic to other sulphonamide medicines. Examples include:

    sulphonamide antibiotics, thiazide diuretics, and sulfonylurea antidiabetes medicines.

Warnings and precautions

Zonisamide Teva belongs to a group of medicines (sulphonamides) which can cause severe allergic reactions, severe skin rashes, and blood disorders, which very rarely can be fatal (see section 4. Possible side effects).

Serious rashes occur in association with Zonisamide Teva therapy, including cases of Stevens-Johnson syndrome.

The use of Zonisamide Teva may lead to high levels of ammonia in the blood which could lead to a change in brain function, especially if you are also taking other medicines which can increase ammonia levels (for example valproate), have a genetic disorder causing build-up of too much ammonia in the body (urea cycle disorder), or if you have liver problems. Tell your doctor immediately if you become unusually drowsy or confused.

Do not give this medicine to children below the age of 6 years because it is not known for this age group whether the potential benefits are greater than the risks.

Other medicines and Zonisamide Teva

Tell your doctor or pharmacist if you are taking, have recently taken or might take any other medicines, including medicines obtained without a prescription.

  • Zonisamide Teva should be used carefully in adults when taken with medicines that can cause kidney stones, like topiramate or acetazolamide. In children, this combination is not recommended
  • Zonisamide Teva could possibly increase your blood levels of medicines like digoxin and quinidine, and so a reduction in their dose may be required
  • other medicines like phenytoin,

    carbamazepine, phenobarbitone and rifampicin can decrease your blood levels of Zonisamide Teva, which may require an adjustment of your dose of Zonisamide Teva.

Zonisamide Teva with food and drink

Zonisamide Teva can be taken with or without food.

Pregnancy, breast-feeding and fertility

If you are planning to become pregnant you should discuss your epilepsy treatment with your doctor as early as possible before you become pregnant.

If you are pregnant, or think you may be pregnant, you must tell your doctor straight away and discuss possible risks the epilepsy medicine you are taking might pose to your unborn baby.

If you are planning a pregnancy, talk to your doctor before you stop contraception and before you become pregnant about the possibility of switching to other suitable treatments. If you are or think you might be pregnant, tell your doctor straight away. You should not stop your treatment without discussing this with your doctor.

Suddenly stopping may lead to breakthrough seizures which may harm you and your unborn baby. It is important that your epilepsy remains well controlled.

Pregnancy

You must only take Zonisamide Teva during your pregnancy if your doctor tells you to. If you are a woman of childbearing age you must use adequate contraception while taking Zonisamide Teva and for one month after stopping Zonisamide Teva.

Talk to your doctor or pharmacist before taking Zonisamide Teva if you:

  • are younger than 12 years old, as you may be at greater risk of decreased sweating, heat stroke, pneumonia and liver problems. If you are younger than 6 years old, Zonisamide Teva is not recommended for you.
  • are elderly, as your dose of Zonisamide Teva may need adjusting, and you may be more likely to develop an allergic reaction, severe skin rash, swelling of the feet and legs, and itchiness when taking Zonisamide Teva (see section 4. Possible side effects).
  • suffer from liver problems, as your dose of Zonisamide Teva may need adjusting.
  • have eye problems such as glaucoma.
  • suffer from kidney problems as your dose of Zonisamide Teva may need adjusting.
  • have previously suffered from kidney stones, as you may be at increased risk of developing more kidney stones. Reduce the risk of kidney stones by drinking sufficient water.
  • live in a place or are on holiday in a place where the weather is warm. Zonisamide Teva can make you perspire less, which can cause your body temperature to increase. Reduce the risk of overheating by drinking sufficient water and keeping cool.
  • are underweight, or have lost a lot of weight as Zonisamide Teva can cause you to lose more weight. Tell your doctor as this may need to be monitored.
  • are pregnant or could become pregnant (see section ‘pregnancy, breast-feeding and fertility’ for further information).

If any of these applies to you, tell your doctor before you take Zonisamide Teva.

Children and adolescents

Talk to your doctor about the following risks:

Preventing overheating and dehydration in children

Zonisamide Teva can cause your child to sweat less and overheat and if your child is not treated this can lead to brain damage and death. Children are most at risk especially in hot weather.

When your child is taking Zonisamide Teva:

  • Keep your child cool especially in hot weather
  • Your child must avoid heavy exercise especially when the weather is hot
  • Give your child plenty of cold water to drink
  • Your child must not take these medicines: carbonic anhydrase inhibitors (like topiramate and acetazolamide), and anticholinergic agents (like clomipramine, hydroxyzine, diphenhydramine, haloperidol, imipramine and oxybutynin).

If your child’s skin feels very hot with little or no sweating, becomes confused, has muscle cramps, or your child’s heartbeat or breathing becomes rapid:

  • Take your child to a cool, shaded place
  • Sponge your child’s skin with cool (not cold) water

    Studies have shown an increased risk of physical birth abnormalities in children of women taking epilepsy medicines during pregnancy. The risk of birth defects or neurodevelopmental disorders (problems with brain development) for your child after taking Zonisamide Teva during your pregnancy is unknown. The risk of physical birth

    abnormalities may increase when more than one epilepsy medicine is used at the same time. Where possible, your doctor should consider using one epilepsy medicine to control your epilepsy.

    More research is needed to better understand whether taking Zonisamide Teva during pregnancy increases the risk of having a baby born with a physical birth abnormality or a learning or thinking disability.

    Studies have showed that babies born to mothers using Zonisamide Teva during pregnancy were smaller than expected for their age at birth, compared with babies born to mothers treated with lamotrigine monotherapy.

    Do not breast-feed whilst taking, or for one month after stopping Zonisamide Teva.

    Make sure you are fully informed about the risks and the benefits of using Zonisamide Teva for epilepsy during pregnancy.

    There are no clinical data available on the effects of Zonisamide Teva on human fertility. Studies in animals have shown changes in fertility parameters.

    Driving and using machines

    Zonisamide Teva may affect your concentration, ability to react/respond, and may make you feel sleepy, particularly at the beginning of your treatment or after your dose is increased. Be especially careful while driving or operating machinery, if Zonisamide Teva affects you in this way.

    Sodium

    This medicine contains less than 1 mmol sodium (23 mg) per capsule, hard, that is to say essentially ‘sodium-free’.

    3

How to take Zonisamide Teva

Always take this medicine exactly as your doctor has told you. Check with your doctor or pharmacist if you are not sure.

When you take Zonisamide Teva on its own:

  • the starting dose is 100 mg taken once a day
  • this may be increased by up to 100 mg at intervals of two weeks
  • the recommended dose is 300 mg once a day.

When you take Zonisamide Teva with other anti-epileptic medicines:

  • the starting dose is 50 mg daily taken in two equal doses of 25 mg
  • this may be increased by up to 100 mg at intervals of one to two weeks
  • the recommended daily dose is between 300 mg and 500 mg

REG0173194 7.2 Approved Page 1 of 3

  • some people respond to lower doses. The dose may be increased more slowly if you experience side effects, are elderly or if you suffer from kidney or liver problems.

Use in children (aged 6 to 11 years) and adolescents (aged 12 to 17 years) weighing at least 20 kg:

  • the starting dose is 1 mg per kg of body weight taken once a day
  • this may be increased by 1 mg per kg of body weight at intervals of one to two weeks
  • the recommended daily dose is 6 to 8 mg per kg for a child with a body weight of up to 55 kg or 300 to 500 mg for a child with a body weight more than 55 kg (which ever dose is lower) taken once a day.

Example: A child who weighs 25 kg should take 25 mg once a day for the first week, and then increase the daily dose by 25 mg at the start of each week until a daily dose between 150 to 200 mg is reached.

If you feel that the effect of Zonisamide Teva is too strong or too weak, talk to your doctor or pharmacist.

  • Zonisamide Teva capsules must be swallowed whole with water
  • do not chew the capsules
  • Zonisamide Teva can be taken once or twice daily, as instructed by your doctor
  • if you take Zonisamide Teva twice a day, take half the daily dose in the morning and half in the evening.

If you take more Zonisamide Teva than you should

If you may have taken more Zonisamide Teva than you should, tell a carer (relative or friend), your doctor or pharmacist

immediately, or contact your nearest hospital casualty department, taking your medicine with you. You may become sleepy and could lose consciousness. You might also feel sick, have a sore stomach, muscle twitches, eye movement, feel faint, have a slowed heart beat, and reduced breathing and kidney function. Do not try to drive.

If you forget to take Zonisamide Teva

  • if you forget to take a dose, don’t worry: take the next dose when it is due
  • do not take double the dose to make up for the forgotten dose.

If you stop taking Zonisamide Teva

  • Zonisamide Teva is meant to be taken as a long-term medicine. Do not reduce your dose or stop your medicine unless your doctor tells you to
  • if your doctor advises you to stop taking Zonisamide Teva your dose will be reduced gradually to lower the risk of more seizures.

If you have any further questions on the use of this medicine, ask your doctor or pharmacist.

4

Possible side effects

Like all medicines, this medicine can cause side effects, although not everybody gets them.

Zonisamide Teva belongs to a group of medicines (sulphonamides) that can cause severe allergic reactions, severe skin rashes, and blood disorders, which very rarely can be fatal.

Contact your doctor immediately if you:

  • have difficulty breathing, a swollen face, lips or tongue, or a severe skin rash as these symptoms may indicate that you are having a severe allergic reaction
  • have signs of overheating - high body temperature but little or no sweating, rapid heartbeat and breathing, muscle cramps, and confusion
  • have thoughts of harming or killing yourself. A small number of people being treated with anti-epileptics such as Zonisamide Teva have had thoughts of harming or killing themselves
  • have pain in your muscles or a feeling of weakness, as this may be a sign of abnormal muscle breakdown which can lead to kidney problems
  • get a sudden pain in your back or stomach, have pain on urinating (passing water) or notice blood in your urine, as this may be a sign of kidney stones.
  • develop visual problems such as eye pain or blurred vision while taking Zonisamide Teva

Contact your doctor as soon as possible if you:

  • have an unexplained skin rash, as this could develop into a more severe skin rash or skin peeling
  • feel unusually tired or feverish, have a sore throat, swollen glands, or find that you bruise more easily, as this may mean you have a blood disorder
  • have signs of increased acid level in the blood - headaches, drowsiness, shortness of breath and loss of appetite. Your doctor may need to monitor or treat this.

Your doctor may decide that you should stop using Zonisamide Teva.

The most common side effects of Zonisamide Teva are mild. They occur during the first month of treatment and usually decrease with continued treatment. In children ages 6 – 17 years old, side effects were consistent with those described below with the following exceptions: pneumonia, dehydration, sweating decreased (common) and abnormal liver enzymes (uncommon).

Very common side effects: may affect more than 1 in 10 people

  • agitation, irritability, confusion, depression
  • poor muscle coordination, dizziness, poor memory, sleepiness, double vision
  • loss of appetite, decreased blood levels of bicarbonate (a substance that prevents your blood from becoming acidic).

Common side effects: may affect up to 1 in 10 people

  • difficulty sleeping, strange or unusual thoughts, feeling anxious or emotional
  • slowed thoughts, loss of concentration, speech abnormalities, abnormal skin sensation (pins and needles), tremor, involuntary movement of the eyes
  • kidney stones
  • skin rashes, itching, allergic reactions, fever, tiredness, flu-like symptoms, hair loss
  • ecchymosis (a small bruise caused by blood leaking from broken blood vessels in the skin)

    • loss of weight, nausea, indigestion, stomach pains, diarrhoea (loose stools), constipation
    • swelling of the feet and legs.

Uncommon side effects: may affect up to 1 in 100 people

  • anger, aggression, thoughts of suicide, suicide attempt
  • vomiting
  • gall bladder inflammation, gallstones
  • urinary stones
  • lung infection/inflammation, urinary tract infections
  • low blood potassium levels,

    convulsions/seizures.

Very rare side effects: may affect up to 1 in 10,000 people

  • hallucinations, memory loss, coma, neuroleptic malignant syndrome (inability to move, sweating, fever, incontinence), status epilepticus (prolonged or repeated seizures)
  • breathing disorders, shortness of breath, inflammation of the lungs
  • inflammations of the pancreas (severe pain in the stomach or back)
  • liver problems, kidney failure, increased blood levels of creatinine (a waste product that your kidneys should normally remove)
  • severe rashes or skin peeling (at the same time you may feel unwell or develop a fever)
  • abnormal muscle breakdown (you may feel pain or weakness in your muscles) which can lead to kidney problems
  • swollen glands, blood disorders (reduction in the number of blood cells, which can make infection more likely and can make you look pale, feel tired and feverish, and bruise more easily)
  • decreased sweating, overheating.
  • glaucoma, which is a blockage of fluid in the eye causing increased pressure in the eye. Eye pain, blurred vision or decreased vision may occur and can be signs of glaucoma.

Reporting of side effects

If you get any side effects, talk to your doctor or pharmacist. This includes any possible side effects not listed in this leaflet. You can also report side effects directly via the Yellow Card Scheme at: www.mhra.gov.uk/yellowcard or search for MHRA Yellow Card in the Google Play or Apple App Store

By reporting side effects you can help provide more information on the safety of this medicine.

5

How to store Zonisamide Teva

Keep this medicine out of the sight and reach of children.

Do not use this medicine after the expiry date which is stated on the blister and carton after EXP. The expiry date refers to the last day of that month.

This medicine does not require any special storage conditions.

Do not use this medicine if you notice any damage to the capsules, blister or carton or any visible signs of deterioration in the medicine. Return the pack to your pharmacist.

Do not throw away any medicines via wastewater or household waste. Ask your pharmacist how to throw away medicines you no longer use. These measures will help protect the environment.

6

Contents of the pack and other information

What Zonisamide Teva contains

  • The active substance is zonisamide. Zonisamide Teva 25 mg Capsules, Hard contain 25 mg of zonisamide.

    Zonisamide Teva 50 mg Capsules, Hard contain 50 mg of zonisamide.

    Zonisamide Teva 100 mg Capsules, Hard contain 100 mg of zonisamide.

  • The other ingredients that are present in the capsule contents are: cellulose,

    microcrystalline, sodium lauryl sulfate, silica, colloidal hydrated and hydrogenated vegetable oil type I.

  • The capsule shell contains: titanium dioxide (E171), gelatin, additionally the 50 mg capsule shell contains black iron oxide (E172) and 100 mg capsule shell contains red iron oxide (E172).
  • The imprinting ink contains shellac, propylene glycol, strong ammonia solution, black iron oxide (E172) and potassium hydroxide.

What Zonisamide Teva looks like and contents of the pack

  • Zonisamide Teva 25 mg hard gelatin size 4 capsules, approx. 14 mm x 5 mm, with white cap and white body, filled with white to off white granulate, printed with “25” on the body.
  • Zonisamide Teva 50 mg hard gelatin size 3 capsules, approx. 16 mm x 6 mm, with grey cap and white body, filled with white to off white granulate, printed with “50” on the body.
  • Zonisamide Teva 100 mg hard gelatin size 1 capsules, approx. 19 mm x 7 mm, with orange cap and white body, filled with white to off white granulate, printed with “100” on the body.

Zonisamide Teva 25 mg Capsules, Hard are packed in blisters of 7, 14, 28, 30, 56, 60 or 100 capsules, hard.

Zonisamide Teva 50 mg Capsules, Hard are packed in blisters of 7, 14, 28, 30, 56, 60 or 100 capsules, hard.

Zonisamide Teva 100 mg Capsules, Hard are packed in blisters of 7, 14, 28, 30, 56, 60, 98, 100 or 196 (98 x 2 - multipack) capsules, hard.

Not all pack sizes may be marketed.

Marketing Authorisation Holder and Manufacturer

Marketing Authorisation Holder

Teva UK Limited, Ridings Point, Whistler Drive, Castleford, WF10 5HX, United Kingdom.

Manufacturer

TEVA Pharmaceutical Works Private Limited Company, Pallagi út 13, 4042 Debrecen, Hungary

This leaflet was last revised in 04/2023

PL 00289/1993

PL 00289/1994

PL 00289/1995

85983_s1

REG0173194 7.2 Approved Page 2 of 3

About this document

Source: MHRA - Medicines and Healthcare products Regulatory Agency (products.mhra.gov.uk) · Marketing authorisation: PL 00289/1995

Last revision stated in the text: April 2023 · MHRA data as of 13 October 2026

Found a mistake? Tell us on the contact page.

The information on this site does not replace the advice of a doctor or pharmacist.

Facts about Zonisamide Teva 100 mg capsules hard

Prescription needed? Yes, prescription-only medicine (POM)
Active substance Zonisamide
Strength 100 mg
Pharmaceutical form Oral capsule
A hard gelatin size 1 capsule, approx. 19 mm x 7 mm, with orange cap and white body, filled with white to off white granulate, printed with “100” on the body.
How is it taken Oral
Excipients Cellulose, microcrystalline, Sodium laurilsulfate, Silica, colloidal hydrated, Hydrogenated vegetable oil Type I, Titanium dioxide (E171), Gelatin, Red iron oxide (E172), Shellac, Propylene glycol, Strong ammonia solution, Black iron oxide, Potassium hydroxide
Pack sizes 56 capsule
Is it available? Listed as available (NHS Dictionary of Medicines and Devices – not a record of current supplies)
Shelf life 2 years
Storage This medicinal product does not require any special storage conditions.
Drug group (ATC) Antiepileptics, other antiepileptics
  1. N Nervous system drugs
    1. N03 Antiepileptics
      1. N03A Antiepileptics
        1. N03AX Other antiepileptics
          1. N03AX15 zonisamide
Marketing authorisation PL 00289/1995 (first authorised 30 July 2020)
Marketing authorisation holder Teva UK Limited
Codes GTIN 5017007019848 · BNF 04080100

Sources: the MHRA product information (products.mhra.gov.uk) and the NHS Dictionary of Medicines and Devices (dm+d), release 10.2.0 of 19 October 2026, NHS Business Services Authority. Contains public sector information licensed under the Open Government Licence v3.0.