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Flecainide (flek-an-ide) is a medicine that can control and prevent abnormal heart rhythms (arrhythmia).
Flecainide is produced and sold by many different companies, and different brands of the same medicine have different names (e.g. Tambocor, Flecatab).
Your child’s doctor will work out the amount (the dose) of flecainide that is right for your child. The dose will be shown on the medicine label. It is important to give your child this medicine exactly as instructed as it can be dangerous if given incorrectly.
Flecainide is usually started at a low dose and slowly increased until your child’s condition is controlled. Your child’s cardiologist (heart specialist) will schedule regular appointments to monitor your child’s condition and to make sure the flecainide is working. It is important you attend every appointment, so your child’s doctor can adjust the dose if needed.
Flecainide is available as 50mg and 100mg tablets. The Royal Children’s Hospital (RCH) pharmacy department also prepare capsules in a range of strengths for patients who have a prescription written by an RCH doctor. Your child’s doctor or pharmacist will advise which product is most suitable for your child. Flecainide should not be prepared by a compounding pharmacy.
Flecainide is usually given two or three times per day, as directed by your doctor.
It is important to give flecainide around the same time each day so it becomes part of your daily routine. If more than one person usually gives your child their medication, make sure that you communicate and write down doses given so that you don’t give extra doses by mistake.
Milk (including breastmilk and infant formula) may reduce the amount of flecainide absorbed from the stomach. Flecainide doses should be given at least 30 minutes either side of milk or milk feeds. It is also best to give flecainide 30 minutes before food as it may numb the mouth for a short time after the dose is given.
You should discuss what to do in the event of a missed or late dose with your child’s cardiologist or pharmacist before leaving hospital. You can ask them to provide you with a written action plan to take home and follow if a dose has been missed. Never give a double dose of flecainide to make up for a missed dose as this can cause changes to your child’s heart rhythm.
It can be dangerous if too much flecainide is given. If you think you may have given your child too much flecainide, call the Poisons Information Centre on 13 11 26 as soon as possible, even if your child shows no symptoms. In the case of an emergency, call an ambulance (000) or take your child to the nearest hospital emergency department. Have the medicine container or packaging with you, even if it is empty, as this information will be useful.
Medicines are designed to make us better, but sometimes they have unwanted effects (side effects). Some side effects will go away with time, or after the dose has been changed. If your child is vomiting or has diarrhoea or they have not eaten for more than 24 hours, this may increase the chance of side effects from flecainide – contact your child’s cardiologist for advice in this situation.
Speak to your child’s doctor if you are worried about any of the following:
Your child may feel dizzy while taking flecainide. Care must be taken with activities like bike riding or climbing, or, for older children, driving or operating heavy machinery.
Contact your doctor or hospital immediately if your child has:
There may be other side effects that are not listed in this fact sheet. If you notice anything unusual or are concerned about your child, contact your doctor.
What if my child vomits after taking flecainide?
If your child spits out the dose or vomits after you have given flecainide, you do not need to give another dose. Give the next dose at the usual time.
Can other medicines be given at the same time as flecainide?
If you are giving other medicines to your child, it is best to separate these from flecainide by an hour. Check with your doctor or pharmacist to ensure other medicines can be used safely with flecainide and make a plan for medication administration times.
My child is a patient of the RCH, how do I order more flecainide capsules?
Patients who have a prescription written by an RCH doctor may have flecainide capsules prepared by the RCH pharmacy department as needed. Please contact the RCH pharmacy department on (03) 9345 5449 or firstname.lastname@example.org to arrange another supply at least five working days before you will run out of capsules.
Developed by The Royal Children's Hospital Pharmacy department, Medication Safety Committee and Cardiology department. We acknowledge the input of RCH consumers and carers.
Developed July 2019.
This information is awaiting routine review. Please always seek the most recent advice from a registered and practising clinician.
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