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Flecainide acetate oral


Standard release formulations of flecainide acetate

Drugs List

  • flecainide 100mg tablets
  • flecainide 50mg tablets
  • Therapeutic Indications


    Arrhythmias associated with Wolff-Parkinson-White Syndrome
    AV nodal reciprocating tachycardia
    Maintenance of normal rhythm after conversion by other means
    Paroxysmal atrial fibrillation with disabling symptoms
    Ventricular arrhythmias
    Ventricular tachycardia, symptomatic and sustained - treatment



    Treatment with oral flecainide should be under direct hospital or specialist supervision for patients with:
    AV nodal reciprocating tachycardia
    Arrhythmias associated with Wolff-Parkinson-White syndrome and similar conditions with accessory pathways
    Paroxysmal atrial fibrillation in patients with disabling symptoms

    Treatment for patients with other indications should be continued to be initiated in hospital.

    Supraventricular arrhythmias
    Initial dosage: 50mg twice daily.
    Maintenance dosage: 50mg twice daily in most cases, although if required the dose may be increased to a maximum of 300mg daily.

    Ventricular Arrhythmias
    Initial dosage: 100mg twice daily.
    Maximum daily dosage: 400mg (normally reserved for patients of large build or where rapid control of arrhythmia is required).

    After three to five days it is recommended that the dosage should be progressively adjusted to the lowest dose which maintains control of the arrhythmia. It may be possible to reduce dose during long term treatment.


    (See Dosage; Adult)

    Plasma elimination of flecainide may be slower in elderly patients and this should be considered when making dosage adjustments.


    Children aged 12 years and over
    (See Dosage; Adult)

    The following alternative dosing schedule may be suitable:
    Arrhythmias associated with accessory conduction pathways, paroxysmal atrial fibrillation, resistant re-entry supraventricular tachycardia, ventricular ectopic beats or ventricular tachycardia
    Children aged 12 years to 18 years
    Initial dose: 50mg to 100mg twice daily, increase if necessary up to 300mg.
    Maximum dose: 300mg daily (400 mg daily for ventricular arrhythmias in heavy built children).
    Children aged 1 month to 12 years (unlicensed)
    2mg/kg two to three times daily. Titrate to response and plasma flecainide concentrations.
    Maximum dose: 8mg/kg daily or 300mg daily.

    For administration by mouth, milk, infant formula and dairy products may reduce the absorption of flecainide - separate doses from feeds.


    Arrhythmias associated with accessory conduction pathways, paroxysmal atrial fibrillation, resistant re-entry supraventricular tachycardia, ventricular ectopic beats or ventricular tachycardia (unlicensed)
    2mg/kg two to three times daily. Titrate to response and plasma-flecainide concentration.

    For administration by mouth, milk, infant formula and dairy products may reduce the absorption of flecainide - separate doses from feeds.

    Patients with Renal Impairment

    In patients with significant renal impairment (creatinine clearance of 35ml/minute or less) the maximum initial dose should be 100mg (or 50mg twice a day).

    Frequent plasma level monitoring is recommended.

    Patients with Hepatic Impairment

    Flecainide elimination from the plasma can be markedly slower in patients with significant hepatic impairment

    Plasma level monitoring is strongly recommended in these circumstances.

    Additional Dosage Information

    Based of PVC suppression:

    Plasma levels of 200 to 1000 nanograms/ml may be needed to achieve maximum therapeutic effect.

    Plasma levels above 700 to 1000 nanograms/ml are associated with an increased risk of adverse effects.


    Bundle branch block where no pacing rescue available
    Cardiac failure
    Haemodynamically significant valvular heart disease
    History of MI with asymptomatic non-sustaining ventricular tachycardia
    History of MI with asymptomatic ventricular ectopy
    Left ventricular dysfunction
    Non paced atrial conduction defects
    Non paced second/third degree AV block
    Non-paced sinus node dysfunction
    Structural cardiac disorder

    Precautions and Warnings

    Children under 12 years
    Predisposition to cardiac failure
    Tobacco smoking
    Cardiac pacemaker
    Cardiac surgery
    Coronary arteriosclerosis
    History of myocardial infarction
    Renal impairment - creatinine clearance below 35ml/minute
    Severe hepatic impairment

    Correct electrolyte disorders before treatment
    Advise ability to drive/operate machinery may be affected by side effects
    Treatment should be initiated in hospital
    Monitor plasma levels and adapt dose in patients with hepatic impairment
    Monitor plasma levels and adapt dose in patients with renal impairment
    Dose adjustment required if patient starts/stops smoking during therapy

    The minor negative inotropic effect of flecainide may be of importance in patients with predisposition to cardiac failure. Use with caution in patients with pre-existing heart disease with cardiac enlargement, a history of myocardial infarction and arterio-sclerotic heart disease as difficulty has been experienced in defibrillating some patients with these conditions.

    Use with caution in patients with permanent pacemaker or temporary pacing electrodes due to flecainide increasing the endocardial pacing threshold (decreases endocardial pacing sensitivity).

    Doubling of either pulse width or voltage is generally sufficient to regain control. Caution during initial implantation as it may be difficult to obtain ventricular thresholds less than 1 volt during flecainide therapy.

    In patients with atrial flutter the use of flecainide has been associated with 1:1 AV conduction following atrial slowing with resultant ventricular acceleration. This effect is usually short lived and abates quickly following cessation of therapy.

    In selected patients with infrequent episodes of symptomatic paroxysmal atrial fibrillation, sinus rhythm can be restored using the 'pill-in-the-pocket' approach involving the patient taking oral flecainide to self treat an episode of atrial fibrillation when it occurs.

    Flecainide may be associated with a 2.2 fold higher rate of mortality or non-fatal cardiac arrest in post-myocardial infarction patients.

    Tobacco smoke may reduce flecainide plasma level. Dosage adjustment may be required if a patient starts or stops smoking during treatment with flecainide.

    Pregnancy and Lactation


    Use flecainide with caution in pregnancy.

    There is no evidence as to drug safety in human pregnancy. Some foetal abnormalities have been seen in some (but not all) animal breeds but the relevance of these findings to humans has not been established. Structural defects observed in animals included club paws, sternebrae and vertebrae abnormalities and pale hearts with contracted ventricular septum. Data has shown that flecainide crosses the placenta to the foetus in patients taking flecainide during pregnancy. As yet, there are no recognisable teratogenic or foetotoxic effects in human pregnancy, however in one case report hyperbilirubinemia of a newborn was reported as an adverse effect of flecainide therapy (Briggs, 2011). Schaefer (2007) recommends close monitoring of the mother's serum concentration in order to minimise foetal adverse effects. Antiarrhythmics can cause arrhythmia and therefore it is important to evaluate the indication when used in pregnancy. Publications have described the successful use of flecainide for the treatment of foetal tachycardia (Briggs, 2011). Schaefer (2007)states that flecainide is one of the class IC antiarrhythmic drugs for choice for treating pregnant women in their second or third trimester and is one of the drugs of second choice for treating foetal supraventricular tachycardia.

    The use of all medication in pregnancy should be avoided whenever possible; particularly in the first trimester. Non-drug treatments should also be considered. When essential, a medication with the best safety record over time should be chosen, employing the lowest effective dose for the shortest possible time. Polypharmacy should be avoided. Teratogens taken in the pre-embryonic period, often quoted as lasting until 14 to 17 days post-conception, are believed to have an all-or-nothing effect. Where drugs have a short half-life, and when the date of conception is certain, this may allow women to be reassured where drug exposure has occurred within this time frame. Further advice may be available from the UK National Teratology Information Service (NTIS) and through ToxBase, available via password on the internet ( ) or if this is unavailable at the backup site ( ).


    Use flecainide with caution in breastfeeding.

    Flecainide is excreted in human milk. Limited information indicates that maternal doses of flecainide up to 200 mg daily produce low levels in milk and should not be expected to cause any adverse effects in breastfed infants, especially if the infant is older than 2 months. The risk of adverse effects to the nursing infant is very small. Hale (2010) comments that no adverse effect in breastfed infants have yet been reported but suggests that infant is observed for dizziness, faintness, dyspnoea, headache, nausea and constipation. Information from LactMed recommends that exclusively breastfed infants should be carefully monitored if this drug is used during breastfeeding, possibly including measurement of serum levels to rule out toxicity. Schaefer (2007) states that within the class IC antiarrhythmic drugs, flecainide is the drug of choice for use in patients who are breastfeeding.

    Neonates, infants born prematurely, those with low birth weight, those with an unstable gastrointestinal function or who have serious illnesses may require special consideration. For any infant, if a drug is prescribed to the nursing mother, it should be at the lowest practical dose and for the shortest time. When drug administration is unavoidable and breastfeeding is to continue, minimisation of exposure of the infant to the drug may sometimes be achieved by timing the maternal doses to just after a feeding episode. Infants exposed to drugs via breast milk should be monitored for unusual signs or symptoms. Interactions between the drug received by the infant from the mother's milk and medication prescribed for the infant should also be considered, for example, when the drug given to the infant may prevent metabolism of the drug received via breast milk.
    Specialist advice is available from the UK Drugs in Lactation Advisory Service at

    Side Effects

    Abdominal pain
    Blurred vision (transient)
    Cardiac failure
    Chest pain
    Congestive cardiac failure
    Corneal deposits
    Double vision
    Gastro-intestinal disturbances
    Hepatic impairment
    Hypersensitivity reactions
    Increase in antinuclear antibodies (ANA)
    Increased sweating
    Increases in hepatic enzymes (reversible)
    Jaundice (reversible)
    Myocardial infarction
    Peripheral neuropathy
    Pro-arrhythmic effects
    Second and third degree AV block
    Sinus arrest
    Sinus pause
    Ventricular tachycardia
    Visual disturbances


    It is strongly recommended that the UK National Poisons Information Service be consulted on cases of suspected or actual overdose where there is doubt over the degree of risk or about appropriate management.

    The following number will direct the caller to the relevant local centre (0844) 892 0111

    Information may be obtained if you have access to ToxBase the primary clinical toxicology database of the National Poisons Information Service. This is available via password on the internet ( ) or if this is unavailable at the backup site ( ).

    Further Information

    Last Full Review Date: September 2013

    Reference Sources

    Drugs During Pregnancy and Lactation: Treatment Options and Risk Assessment, 2nd edition (2007) ed. Schaefer, C., Peters, P. and Miller, R. Elsevier, London.

    Drugs in Pregnancy and Lactation: A Reference Guide to Fetal and Neonatal Risk, 9th edition (2011) ed. Briggs, G., Freeman, R. and Yaffe, S. Lippincott Williams & Wilkins, Philadelphia.

    Martindale: The Complete Drug Reference, 37th edition (2011) ed. Sweetman, S. Pharmaceutical Press, London.

    Medications and Mothers' Milk, 14th Edition (2010) Hale,T. Hale Publishing, Amarillo, Texas.

    Summary of Product Characteristics: Flecainide acetate 50mg tablets. Actavis UK Ltd. Revised August 2012.
    Summary of Product Characteristics: Flecainide acetate 100mg tablets. Actavis UK Ltd. Revised August 2012.

    Summary of Product Characteristics: Flecainide acetate 50mg tablets. Aurobindo Pharma - Milpharm Ltd. Revised September 2012.
    Summary of Product Characteristics: Flecainide acetate 100mg tablets. Aurobindo Pharma - Milpharm Ltd. Revised September 2012.

    Summary of Product Characteristics: Flecainide acetate 50mg tablets. Meda Pharmaceuticals. Revised February 2010.
    Summary of Product Characteristics: Flecainide acetate 100mg. Meda Pharmaceuticals. Revised May 2013.

    Summary of Product Characteristics: Flecainide acetate 100mg tablets. Zentiva. Revised February 2011.

    Summary of Product Characteristics: Tambocor 50mg tablets. Meda Pharmaceuticals Ltd. Revised March 2012.
    Summary of Product Characteristics: Tambocor 100mg tablets. Meda Pharmaceuticals Ltd. Revised March 2012.

    The Renal Drug Handbook. 3rd edition. (2009) ed. Ashley, C and Currie, Radcliffe Publishing Ltd, Abingdon.

    NICE Evidence Services Available at: Last accessed: 24 August 2017

    Specialist Pharmacy Service (SPS)
    Available at:
    What are the clinically significant drug interactions with tobacco smoking? Last revised: July 2020
    Last accessed: 07 December 2020

    US National Library of Medicine. Toxicology Data Network. Drugs and Lactation Database (LactMed).
    Available at:
    Flecainide. Last revised: September 07, 2013.
    Last accessed: September 16, 2013

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