Ethosuximide

In Aotearoa New Zealand, ethosuximide is available as 250 mg capsules and a 250 mg per 5 mL liquid syrup.

• The dose of ethosuximide will be different for different people, depending on your age and response to the medication or if you're taking other medicines.
• Your healthcare provider will start you on a low dose and increase your dose slowly over a few weeks.
• Always take your ethosuximide exactly as your healthcare provider has told you. The pharmacy label on your medicine will tell you how much to take, how often to take it, and any special instructions.

• Timing: Ethosuximide is usually taken twice a day, usually about 10 to 12 hours apart. Try to take it at the same times each day, as this will help you to remember to take your doses regularly.
• Capsules: Swallow your capsules whole with a drink of water.
• Food: You can take ethosuximide with or without food.
• Missed dose: If you forget to take your dose, take it as soon as you remember if it's within 4 hours of when your dose was due. But if more than 4 hours have passed since when the dose was due, just take the next dose at the usual time. Don't take extra doses to make up for a forgotten dose. If you're not sure what to do, ask your healthcare provider.

For information on how to give ethosuximide to children, see ethosuximide information for parents and carers.(external link) 

Here are some things to know when you're taking ethosuximide. Other things may be important as well, so ask your healthcare provider what you should know about.

• Alcohol: Avoid drinking alcohol while you're taking ethosuximide. Alcohol can increase your chance of side effects such as drowsiness.
• Tell all your healthcare providers that you're taking ethosuximide: This includes your doctors, nurses, pharmacists and dentists.
• Driving: Avoid driving and doing other tasks or actions that need you to be alert until you see how this medicine affects you.
• Other medicines: Ethosuximide can interact with other medicines. Tell your healthcare provider or pharmacist about all medicines you're taking including over the counter medicines, herbal and complementary medicines or recreational drugs. 
• Keep taking ethosuximide every day: See tips to help you remember to take your medicines regularly.  It may take a few weeks before you notice the full benefits of ethosuximide.
• Don't stop taking ethosuximide suddenly: Talk to your healthcare provider or nurse before stopping.
• Contraception: Use 2 forms of effective contraception (eg, condoms and another kind) for the whole time you're taking ethosuximide. Read more about epilepsy and contraception.

   

If you are planning a pregnancy

• It's important to contact your healthcare provider 6 to 12 months before you want to become pregnant. Read more about epilepsy and pregnancy.
• If you become pregnant: Contact your healthcare provider immediately but don't stop taking ethosuximide until you've discussed it with them. There are risks to yourself and your unborn child from uncontrolled epilepsy.
• For more information, read:
  • medicines for epilepsy, mental health and pain can harm your unborn baby(external link)
  • epilepsy medicines and pregnancy.(external link)

Like all medicines, ethosuximide can cause side effects, although not everyone gets them. If you're concerned about any symptoms you think might be related to your medicine, talk to your healthcare provider. The following information offers some guidance but doesn't include all possible side effects.

Common side effects

Tell your healthcare provider if these side effects bother you.

• Sore stomach, feeling sick (nausea) or being sick (vomiting) or runny poo (diarrhoea).
• Feeling sleepy. Be careful when driving or using tools until you know how this medicine affects you.
• Feeling dizzy or lightheaded. These effects put you at risk of falls, and injuries especially if you’re an older adult. Don’t drink alcohol – it makes these effects worse.
• Headache.
• Muscle weakness.
• Hiccups.

Tell your healthcare provider immediately or phone Healthline free on 0800 611 116 if these occur

• Loss of coordination, trouble concentrating
• Skin rash, skin peeling or blisters
• Mood changes, low mood, thoughts or talk of suicide and self-harm
• Signs of problems with your blood cells, such as mouth ulcers, fever, chills, sore throat, unexplained bruising or bleeding.

Read more about medicines and side effects and reporting a reaction you think might be a side effect.