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Drug Class: Commonly Known As: Category:
Cardiovascular Agent Tambocor Adult, Children

Flecainide - Side Effects, Precautions, and Contraindications

What side effects can Flecainide cause?

Common side effects include:

  • 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, stomach upset (constipation, diarrhea)
  • Decreased appetite

For infants and young children, blood tests may be required to monitor the level of flecainide. A gene test may also be required to guide drug dosing and for making dose adjustments.

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.

Before taking Flecainide, what precautions must I follow?

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.

What food or medicine must I avoid when I take Flecainide?

Some medications may interact with Flecainide 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.

Flecainide - Additional Information

  • Updated on Wednesday, September 30, 2020
  • Article contributed by PSS National Medication Information Workgroup PSS National Medication Information Workgroup

    The information provided is not intended as medical advice. Terms of use. Information provided by SingHealth

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