About zonisamide

If you have epilepsy, it means that you have had repeated seizures. A seizure is a short episode of symptoms caused by a burst of abnormal electrical activity in your brain. Different parts of the brain control different parts and functions of your body. Therefore, the symptoms that occur during a seizure depend on where the abnormal burst of electrical activity occurs. Symptoms that may occur during a seizure can affect your muscles, sensations, behaviour, emotions, consciousness, or a combination of these. With a focal (sometimes called 'partial') seizure, the burst of electrical activity stays in one part of the brain. Therefore, you tend to have localised or 'focal' symptoms.

Zonisamide works by stabilising the electrical activity in your brain, which prevents the seizures from occurring.

Before taking zonisamide

Some medicines are not suitable for people with certain conditions, and sometimes a medicine may only be used if extra care is taken. For these reasons, before you start taking zonisamide it is important that your doctor or pharmacist knows:

• If you are under 18 or over 65 years of age.
• If you have kidney or liver problems.
• If you have ever had kidney stones.
• If you are pregnant, trying for a baby or breast-feeding.
• If you have ever had an allergic reaction to this or to any other medicine. This is especially important if you have ever had an allergic reaction to a sulphonamide antibiotic, a thiazide diuretic, or a sulfonylurea antidiabetic medicine.

How to take zonisamide

• Before you start this treatment, read the manufacturer's printed information leaflet from inside the pack. The leaflet will give you more information about the brand of zonisamide you have been given, and a full list of possible side-effects from taking it.
• Take zonisamide exactly as your doctor has told you. Your doctor or pharmacist will tell you how many capsules to take and when to take them. Your dose will also be on the label of your pack. You need to take zonisamide regularly every day to prevent the seizures from occurring.
• When you first start taking zonisamide, your doctor will give you a small dose and then gradually increase your dose. This allows your doctor to make sure that you have the dose that helps your condition and avoids any unwanted symptoms.
• You may take zonisamide before, during or after meals.
• Try to take your doses of zonisamide at the same times each day. This will help you to avoid missing any.
• If you do forget to take a dose, take it as soon as you remember (unless it is nearly time for your next dose, in which case leave out the missed dose). Do not take two doses together to make up for a forgotten dose.

Getting the most from your treatment

• Make sure you drink plenty of water while you are on zonisamide. This is because some people who have taken zonisamide have developed kidney stones - drinking plenty of water will help to prevent this. Occasionally, people taking zonisamide have had heat stroke - drinking plenty of water will also help to prevent this. This is especially important if you work in a hot environment or the weather is warm.
• Try to keep your regular appointments with your doctor. This is so your doctor can check on your progress.
• When you first start a new treatment for epilepsy there may be a change in the number or type of seizures you experience. Your doctor will advise you about this.
• If you buy any medicines, check with a pharmacist that they are suitable for you to take. This is because some medicines and herbal remedies (such as St John's wort) should not be taken with zonisamide.
• If you are a woman, your doctor will advise you about which methods of contraception are suitable for you. If you want to have a family, make sure you discuss this with your doctor well in advance of becoming pregnant. This is so that you can be given advice from a specialist before you become pregnant. If you become pregnant while you are taking zonisamide, you must tell your doctor straightaway.
• If you drink alcohol, ask your doctor for advice about taking zonisamide and alcohol. Drinking alcohol may not be recommended for you.
• While you are taking zonisamide, there is a small risk that you may develop mood changes or distressing feelings, and thoughts about suicide. If this happens, you must tell your doctor straightaway.
• If you are having an operation or dental treatment, tell the person carrying out the treatment that you are taking zonisamide.
• People with epilepsy must stop driving at first. Your doctor will advise you about when it may be possible for you to resume driving again. This will usually be after a year free of seizures.
• Do not stop taking this medicine unless your doctor tells you to do so. Stopping zonisamide suddenly can cause problems and your doctor will probably want you to reduce your dose gradually if this is necessary.

Can zonisamide cause problems?

Along with their useful effects, most medicines can cause unwanted side-effects although not everyone experiences them. These usually improve as your body adjusts to the new medicine, but speak with your doctor or pharmacist if any of the following side-effects continue or become troublesome.

Important: if you notice any of the following, contact your doctor (or go to your local accident and emergency department) straightaway:

• Any difficulty breathing, or signs of swelling around your mouth or face.
• A skin rash.
• A high temperature or swollen glands.

If you experience any other symptoms which you think may be due to this medicine, speak with your doctor or pharmacist.

How to store zonisamide

• Keep all medicines out of the reach and sight of children.
• Store in a cool, dry place, away from direct heat and light.

Important information about all medicines