Medication Information Leaflet

What is this medication for?

This medication is used to suppress and prevent the recurrence of abnormal heart rhythm. It works by slowing an overactive heart and correcting irregular heartbeats to a normal rhythm so that the heart works properly to pump blood.

How should I take or use this medication?

• Do not stop taking your medication without checking with your healthcare professional.
• You may take this medication with or without food.
• The doctor may adjust the dose based on your condition. Do not take this medication more often than directed and do not stop until instructed by your doctor.

What should I do if I forget to take or use this medication?

If you forget to take a dose, take it as soon as you remember. If it is almost time for your next dose, skip the missed dose. Then take your next dose at the usual time. Do not take two doses to make up for the missed dose.

What precautions should I take when taking or using this medication?

Inform your healthcare professional if:

• You are allergic to this medication or any of the other ingredients of this medication.
• You are pregnant, planning to become pregnant, or breastfeeding.
• You are taking any other medications, including supplements, traditional medications and herbal remedies.
• You have kidney or liver disease.
• You have a heart condition known as heart failure, or recently had a heart attack.
• You have a pacemaker or defibrillator.
• You have myasthenia gravis (a disease that causes muscle weakness)

What are some common side effects of this medication?

• Headache, dizziness
  • Try to avoid sudden changes in posture – stand up slowly from sitting or lying positions, and sit or lie down if feeling giddy.
• Problems with your vision – sudden change (blurring) in eyesight, yellow vision
  • Do not drive or operate tools or heavy machinery if your vision is affected. Your doctor may also recommend an eyesight test to monitor for such side-effects.
• Nausea, vomiting
• Dry mouth, changes in taste

What are some rare but serious side-effects that I need to seek medical advice immediately?

It is very important that you are on regular follow-up with your doctor to monitor for any possible side-effects. Inform your healthcare professional if you have any of the following side-effects.

This medication may worsen existing abnormal heart rhythm, or cause new irregular heartbeats. Symptoms of abnormal heart rhythm include one or more of the following:

• Irregular heartbeat e.g. slowed heartbeat or palpitations
• Severe dizziness or fainting spells
• Difficulties in breathing or chest pain

The symptoms of a drug allergy include one or more of the following:

• Swollen face/eyes/lips/tongue
• Difficulty in breathing
• Itchy skin rashes over your whole body

If you experience any of these symptoms, you should stop your medication and see your healthcare professional immediately.

What food or medication should I avoid when I take or use this medication?

Avoid taking grapefruit when you are taking this medication as grapefruit may interact with your medication and increase the risk of side-effects.

Some medications may interact with Propafenone and affect their effectiveness or increase the risk of side-effects. However, these medications may also be important for your treatment. Inform your healthcare professional of the other medications you are currently taking. Examples include:

• Medications for bacterial infections (e.g. clarithromycin, erythromycin)
• Medications for fungal infections (e.g. itraconazole, ketoconazole)
• Medications for viral infections (e.g. Ritonavir)

Consult your healthcare professional if you are unsure whether your existing medications can be taken together with this medication.

How should I store this medication?

Store in a cool and dry place, away from direct sunlight.

Keep this medication away from children.
 

How do I throw away this medication safely?

Pack this medication into a black trash bag and seal it tightly before throwing into the rubbish chute or bin.

Disclaimer

Please take note that the above is not a complete list of all possible side effects. If you have any concerns about your medication or if you have other side effects that you think are caused by this medication, please consult your doctor or pharmacist.

If you take more than the recommended dose, please seek medical advice immediately. The information provided on this page does not replace information from your healthcare professional. Please consult your healthcare professional for more information.

This article is jointly developed by members of the National Medication Information workgroup. The workgroup consists of cluster partners (National Healthcare Group, National University Health System and SingHealth), community pharmacies (Guardian, Unity and Watsons) and Pharmaceutical Society of Singapore. The content does not reflect drug availability and supply information in pharmacies and healthcare institutions. You are advised to check with the respective institutions for such information.

Last updated on March 2025