Zonisamide is used on its own or together with other medicines to treat epilepsy (also known as fits or seizures).
Take Zonisamide exactly as directed by your doctor or according to the instructions on the label. Do not take more or less than instructed by your doctor.
You may take this medicine with or without food. Try to take it at the same time each day.
Zonisamide is available as a capsule, tablet or oral suspension.
If you are taking the capsule, swallow it whole with a glass of water. Do not chew, crush or break the capsule.
If you are taking an oral suspension, shake the bottle well before you take it to ensure that the liquid is evenly mixed. Use the oral syringe provided to measure your dose. The oral suspension may be taken directly from the syringe followed by a glass of water. Alternatively, the oral suspension may be mixed with a glass of water or orange juice. Refer to the package insert for directions on how the oral syringe should be used. Do not mix or take this medicine with carbonated drinks such as sparkling water.
The oral suspension may also be administered via a feeding tube. Flush the tubing 3 times (with at least 5 mL of water for each rinse) immediately after each dose of this medicine to ensure that the full dose is taken.
The dose of this medicine will be decided by your doctor. Your doctor will advise you on the treatment timeframe depending on your response to the medication.
Zonisamide must be taken regularly for it to be effective. Continue taking this medicine even when you feel better. Do not stop taking it suddenly as this may worsen your condition.
Take the missed dose as soon as you remember. If it is almost time for your next dose, skip the missed dose and return to your normal dosing schedule.
DO NOT double a dose under any circumstances.
If you often forget to take your medicine, let your doctor and pharmacist know.
Do not take Zonisamide if you ever had an allergic reaction (e.g. rashes, breathlessness, swollen eyes) to this medicine or sulfonamide drugs such as sulfonamide antibiotics.
Inform your doctor if you have the following conditions:
- personal or family history of kidney stones
- history of eye problems
- inherited problems of metabolism
- excess calcium in the urine
- at risk of acidosis (too much acid in the body) e.g. severe lung disease, undergoing ketogenic diet, diarrhoea
- liver disease
- kidney disease
Let your doctor know if you are pregnant or breastfeeding.
It is important that you do not get pregnant while taking Zonisamide. You must use proven birth control methods during therapy with this medicine and for 1 month after stopping the treatment. You may wish to discuss reliable methods of birth control with your doctor.
Be sure to check with your doctor or pharmacist before giving this medicine to a child or the elderly. Children and elderly people may be more sensitive to the side effects.
Avoid exposure to excessive temperatures and strenuous physical activities, particularly for children.
Drink plenty of water while you are being treated with Zonisamide to reduce the risk of developing kidney stones and overheating.
Why is it important to keep my appointments with the doctor?
Keep your appointments with your doctor. Your doctor needs to monitor your condition and check your response to the medication regularly.
- Routine tests (e.g. kidney function, electrolyte levels) may be done while you are being treated with this medicine. Your doctor will advise you about how often you need to have these tests.
- Regular monitoring for signs of depression, unusual changes in behaviour, decreased sweating and overheating (particularly in children) may also be needed.
Zonisamide may cause drowsiness, dizziness, sleepiness, or difficulty with concentration. If affected, do not drive or take part in any activity in which you need to be alert.
Other side effects include any of the following: nausea, diarrhoea, stomach pain, indigestion, constipation, vomiting, decreased or loss of appetite, difficulty sleeping, tremor, irritability, anxiety, and hair loss.
Some side effects may need immediate medical help. Alert your doctor quickly if you experience any of the following:
- rashes, breathlessness, swelling of the face, eyes or mouth
- having thoughts of self-harm
- unusual changes in mood or behaviour (being too depressed, agitated, or having compulsive and impulsive behaviour)
- changes in your eyesight e.g. eye pain, double or blurred vision
- unusual bleeding or bruising, frequent or persistent sore throat with fever
- unexplained weight loss
- severe muscle pain or weakness with or without fever
- high body temperature but with little or no sweat, feeling confused, muscle cramps
- fast heartbeat and breathing, shortness of breath, feeling very tired or weak
- signs of kidney stones e.g. sudden back or stomach pain, pain while urinating, blood in the urine
- yellowing of the skin or eyes, swelling of the stomach, tiredness
- rashes with peeling of the skin or blistering of the lips, mouth or eyes accompanied by fever
Inform your doctor if any of these side effects do not go away or are severe, or if you experience other side effects.
Inform your doctor and pharmacist if you are taking any of these medicines:
- other medicines for epilepsy (fits or seizures) e.g. topiramate, phenytoin, carbamazepine, phenobarbital
- rifampicin (medicine to treat TB, an infection known as tuberculosis)
- acetazolamide (water pill or medicine for water retention)
- medicines that can cause drowsiness or affect your concentration
This list does not include all medicines that may interact with Zonisamide.
Always notify your doctor and pharmacist if you are taking any other medicines, including herbal tonics such as traditional Chinese medicines, supplements and medicines that you buy without a prescription.
Store in a cool, dry place away from the reach of children.
Protect from light and moisture.
Medicines must not be used past the expiry date.