Mexiletine - oral

Patient Medicine Information
Why do I need this medicine?
Mexiletine is used to treat abnormally fast heartbeat that originates from the lower chambers of the heart.

This medicine may be used to treat other conditions as decided by your doctor.
How do I take this medicine?
Take Mexiletine 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.

This medicine should be taken with food or immediately after a meal. Try to take it at the same time each day.

Mexiletine must be taken at regularly for it to be effective. Continue to take this medicine even when you feel better. Do not stop taking it unless instructed by the doctor.
What should I do if I have forgotten to take this medicine?
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.
When should I not use this medicine?
Alert your doctor if you have other heart disease as Mexiletine may not be suitable for you.
What should I take note of while taking this medicine?
Inform your doctor if you have the following conditions:

- liver disease
- epilepsy (fits or seizures)
- low potassium or magnesium levels in the blood

Let your doctor know if you are pregnant or breastfeeding.

For as long as you are taking Mexiletine, you may need to have liver function tests and an electrocardiogram or ECG (recording of electrical activity of the heart) to check your body's response to the medicine. Your doctor will advise you how often you need to have these tests.
What side effects could I experience?
Mexiletine may cause dizziness, lightheadedness and some problems with your eyesight. 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: stomach discomfort, nausea, vomiting, constipation or diarrhoea, weakness, nervousness, difficulty sleeping, tremor and difficulty in controlling movements such as unsteadiness in walking.

Inform your doctor if any of these side effects do not go away or are severe, or if you experience other side effects.
Can I take this with other medicines?
Inform your doctor and pharmacist if you are taking any of these medicines:

- other medicines for heart disease e.g. amiodarone, verapamil, quinidine
- medicines for epilepsy (fits or seizures) e.g. phenytoin, phenobarbital, carbamazepine
- medicines for depression e.g. fluoxetine, fluvoxamine
- medicines for pain relief e.g. morphine, oxycodone, fentanyl
- medicines for asthma e.g. theophylline
- medicines for TB e.g. rifampicin
- medicines for stomach disorder e.g. cimetidine

This list does not include all medicines that may interact with Mexiletine.

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.
What special dietary instructions should I follow?
Avoid foods that may affect the acidity of your urine. Ask your doctor about the types of food you should avoid.

Avoid alcohol.
How should I store this medicine?
Store in a cool, dry place away from the reach of children.

Medicines must not be used past the expiry date.
This information is independently developed by MIMS based on mexiletine - oral and is provided for your reference only. It is not a replacement for and should only be used in conjunction with full consultation with a licensed healthcare professional, the information provided by your pharmacist and/or the manufacturer of the medication. It may not contain all the available information you require and cannot substitute professional medical care, nor does it take into account all individual circumstances. Although great effort has been made to ensure content accuracy, we shall not be held responsible or liable for any claims or damages arising from the use or misuse of the information contained herein, its contents or omissions, or otherwise. Copyright © 2020 MIMS. All rights reserved. Powered by
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