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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 of flecainide include:

  • Dizzy or lightheadedness. Try to avoid sudden changes in posture – stand up slowly, and sit or lie down if feeling giddy
  • Feeling weak or tired, lack of energy
  • Decreased appetite. Eat small, but frequent meals.
  • Nausea, vomiting, stomach discomfort, diarrhoea or constipation.

Inform your doctor if any of the side effects above become serious or bothersome.

There are some potentially serious, but rare side effects that may be experienced:

  • Changes to your heartbeat, where it starts to pound / beat faster or slower than usual, chest pain, difficulty breathing and feeling faint.
  • Signs of liver problems e.g. yellowing of the skin or whites of the eyes, severe stomach pain, severe nausea / vomiting

Sometimes, flecainide may also cause visual disturbances e.g. blurred (fuzzy) or double vision, difficulty focusing.

Stop the medication and inform your doctor immediately if the side effects above occur, or if you experience any other side effects and allergic reactions (e.g. rash, swelling of the eyes and lips, difficulty breathing).

Before taking Flecainide, what precautions must I follow?

​Check with the doctor or pharmacist if any other medication, supplements or herbal products is to be taken

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

Separate the administration of flecainide from the following food by at least 1-2 hours as it may affect the absorption of flecainide:

  • Milk (including Breast milk and infant formula)
  • Dairy products (e.g. Cheese, yoghurt)

For babies / infants, report any change in dietary milk intake to the doctor as dose adjustments may be needed

Flecainide - Additional Information

Blood tests may be required to monitor the level of flecainide, particularly in infants and young children.

A gene test may also be required to guide drug dosing and for making dose adjustments.
  • Updated on Thursday, April 19, 2018
  • Article contributed by Pharmacy Department KK Women's and Children's Hospital

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

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