Medication Guide App

Flecainide Side Effects

Not all side effects for flecainide may be reported. You should always consult a doctor or healthcare professional for medical advice. Side effects can be reported to the FDA here.

For the Consumer

Applies to flecainide: oral capsule extended release, oral tablet

In addition to its needed effects, some unwanted effects may be caused by flecainide. In the event that any of these side effects do occur, they may require medical attention.

You should check with your doctor immediately if any of these side effects occur when taking flecainide:

More common
  • Difficult or labored breathing
  • dizziness, fainting, or lightheadedness
  • fast, irregular, pounding, or racing heartbeat or pulse
  • shortness of breath
  • tightness in the chest
  • wheezing
Less common
  • Burning, crawling, itching, numbness, prickling, "pins and needles", or tingling feelings
  • chest pain
  • fainting
  • feeling of warmth
  • fever
  • increased sweating
  • partial or slight paralysis
  • redness of the face, neck, arms, and occasionally, upper chest
  • shakiness and unsteady walk
  • shakiness in the legs, arms, hands, or feet
  • swelling of the feet or lower legs
  • trembling or shaking of the hands or feet
  • unsteadiness, trembling, or other problems with muscle control or coordination
Rare
  • Arm, back, or jaw pain
  • black, tarry stools
  • bleeding gums
  • blood in the urine or stools
  • blurred vision
  • chest discomfort
  • chest tightness or heaviness
  • chills
  • confusion
  • convulsions
  • cough
  • decrease in the frequency of urination
  • decrease in urine volume
  • difficulty in passing urine (dribbling)
  • difficulty with breathing
  • dizziness, faintness, or lightheadedness when getting up suddenly from a lying or sitting position
  • frequent urination
  • general feeling of discomfort or illness
  • headache
  • increased volume of pale, dilute urine
  • nausea
  • nervousness
  • noisy breathing
  • painful or difficult urination
  • pinpoint red spots on the skin
  • pounding in the ears
  • sensation of pins and needles
  • slow or fast heartbeat
  • sore throat
  • sores, ulcers, or white spots on the lips or in the mouth
  • stabbing pain
  • sweating
  • swollen glands
  • thickening of bronchial secretions
  • troubled breathing
  • unusual bleeding or bruising
  • unusual tiredness or weakness
  • yellow eyes or skin

Some of the side effects that can occur with flecainide may not need medical attention. As your body adjusts to the medicine during treatment these side effects may go away. Your health care professional may also be able to tell you about ways to reduce or prevent some of these side effects. If any of the following side effects continue, are bothersome or if you have any questions about them, check with your health care professional:

More common
  • Blurred vision or seeing spots
Less common
  • Abdominal or stomach pain
  • acid or sour stomach
  • anxiety or mental depression
  • belching
  • constipation
  • continuing ringing or buzzing or other unexplained noise in the ears
  • depression
  • diarrhea
  • feeling of constant movement of self or surroundings
  • general feeling of discomfort or illness
  • hearing loss
  • heartburn
  • indigestion
  • lack or loss of strength
  • loss of appetite
  • sensation of spinning
  • sleepiness or unusual drowsiness
  • sleeplessness
  • skin rash
  • stomach discomfort, upset, or pain
  • trouble with sleeping
  • unable to sleep
  • weight loss
Rare
  • Bloated
  • change in color vision
  • change in taste
  • cracks in the skin
  • decreased awareness or responsiveness
  • decreased interest in sexual intercourse
  • difficulty seeing at night
  • difficulty with moving
  • dry mouth
  • excess air or gas in the stomach or intestines
  • eye pain or irritation
  • false or unusual sense of well-being
  • feeling of unreality
  • full feeling
  • hair loss or thinning of the hair
  • hives or welts
  • inability to have or keep an erection
  • increased sensitivity of the eyes to sunlight
  • itching skin
  • joint pain
  • lack of feeling or emotion
  • loss in sexual ability, desire, drive, or performance
  • loss of heat from the body
  • loss of memory
  • muscle aching or cramping
  • muscle pain or stiffness
  • passing gas
  • problems with memory
  • red, swollen skin
  • scaly skin
  • sense of detachment from self or body
  • severe sleepiness
  • swollen joints
  • swollen lips, mouth, or tongue
  • uncaring uncontrolled eye movements

For Healthcare Professionals

Applies to flecainide: oral tablet

General

The Cardiac Arrhythmia Suppression Trial (CAST) revealed significantly higher mortality associated with flecainide in patients with a recent history (more than six days but less than two years prior to study) of myocardial infarction (MI) and non-life-threatening ventricular ectopy relative to placebo (5.1% versus 2.3%). The risk of death relative to placebo in patients with a recent history of Q-wave MI and non-Q-wave MI is 8.7 and 1.7, respectively. Use of flecainide in this context is potentially harmful.

Side effects are more likely when plasma flecainide concentrations are greater than 1.0 mcg/mL.[Ref]

Cardiovascular

Risk factors for a proarrhythmic effect include underlying congenital or structural heart disease.

A case of "pseudoinfarction" has been reported in which flecainide induced a transient right bundle branch block with a focal block in the septal fibers of the left bundle branch system. An electrocardiogram (ECG) also revealed ST segment elevations and a Q-wave pattern, consistent with septal infarction. The patient did not have a myocardial infarction by enzyme studies, and the ECG abnormalities resolved after discontinuation of flecainide.

One patient with a history of ischemic congestive heart failure, myocardial infarction (MI), and ventricular arrhythmias developed profound cardiogenic shock without evidence of MI or a new or worsened ventricular arrhythmia. The associated serum flecainide concentration was 1.8 mcg/mL.[Ref]

Cardiovascular side effects including arrhythmias are the most serious side effects. Flecainide may cause or exacerbate arrhythmias in 1% of patients with preexisting paroxysmal supraventricular tachycardia and in 7% of patients with paroxysmal atrial fibrillation. Flecainide may also exacerbate arrhythmias in 7% to 13% of patients with preexisting sustained or nonsustained ventricular arrhythmias.

Flecainide-induced arrhythmias include sinus bradycardia or arrest in 2%, bundle branch blocks in 1%, increased premature ventricular depolarizations in 1%, ventricular tachycardia or fibrillation in 0.5%, and sudden death in 0.2% of patients. New ventricular arrhythmias have been reported in 3.4% of patients.

Flecainide may cause prolongation of the PR, QRS, and corrected QT intervals. Most of the QT interval prolongation is attributable to widening of the QRS complex rather than prolongation of the JT interval. Rare cases of torsades de pointes have been reported.

Exacerbation of congestive heart failure is rare and only occurs in about 0.5% and 9% of patients with preexisting supraventricular arrhythmias and ventricular arrhythmias, respectively. Hypotension is almost exclusively associated with intravenous administration of flecainide.[Ref]

Nervous system

Flecainide may exacerbate myasthenia gravis.

At least 6 cases of flecainide-induced peripheral neuropathy (sensory loss) have been reported and it appears to develop after prolonged use ( 2 to 10 years). Following discontinuation of flecainide therapy, symptoms (e.g., lower-extremity weakness and/or paresthesias, gait disturbance) resolved over 3 to 6 months. However, in some cases the neuropathy did not resolve after discontinuation of flecainide.[Ref]

Nervous system side effects, such as dizziness and visual disturbances (including blurred vision, decreased acuity, and scotomata) occur in 13% to 28% of patients who are taking flecainide doses of 400 mg per day. Transient headaches, asthenia, feelings of a thick tongue or lips, fatigue, paresthesias, and tremors have been reported in 2% to 10% of patients.[Ref]

Gastrointestinal

Gastrointestinal side effects include abdominal pain, nausea, and constipation in 1% to 4% of patients. Diarrhea occurs rarely.[Ref]

Musculoskeletal

Musculoskeletal side effects including weakness has been reported and may be more likely in patients with underlying muscular disorders.[Ref]

A 33-year-old woman with atrial fibrillation, mitral valve prolapse, and a congenital muscle fiber disproportion myopathy developed muscle weakness which partially resolved after flecainide dosage reduction and completely resolved after substitution of flecainide with other antiarrhythmic agents.[Ref]

Ocular

High performance liquid chromatographic analysis of excised corneal deposits in one patient revealed opacities with the same chromatographic characteristics of flecainide.[Ref]

Ocular side effects are limited to rare cases of corneal deposits.[Ref]

Genitourinary

Genitourinary side effects including complaints of impotence are reported in 4% of patients. A case of urinary retention associated with flecainide has been reported.[Ref]

Class I antiarrhythmic agents such as flecainide have local anesthetic and anticholinergic properties which may rarely cause urinary retention.[Ref]

Respiratory

A case of reversible flecainide-induced pneumonitis was reported in a 61-year-old man with a remote history of pulmonary tuberculosis. A complete infectious disease work-up was negative. Serial bronchial-alveolar lavages and chest radiographs were consistent with a drug-induced process.[Ref]

Respiratory side effects are extremely rare.[Ref]

Hematologic

One patient developed leukopenia after 5 months of flecainide therapy. The leukopenia resolved after drug discontinuation and did not recur when flecainide was reinstituted. The leukopenia may have been due to a concurrent viral infection.[Ref]

Hematologic side effects are extremely rare.[Ref]

Hepatic

Hepatic side effects including enzyme concentration elevations have been reported in rare cases.[Ref]

Psychiatric

Psychiatric side effects including paranoid psychosis was reported in a 62-year-old patient receiving flecainide for the treatment of malignant neuropathic pain.[Ref]

References

1. Tjandra-Maga TB, Verbesselt R, Van Hecken A, Mullie A, De Schepper PJ "Flecainide: single and multiple oral dose kinetics, absolute bioavailability and effect of food and antacid in man." Br J Clin Pharmacol 22 (1986): 309-16

2. Greenberg HM, Dwyer EM, Hochman JS, Steinberg JS, Echt DS, Peters RW "Interaction of ischaemia and encainide/flecainide treatment: a proposed mechanism for the increased mortality in CAST I." Br Heart J 74 (1995): 631-5

3. Akiyama T, Pawitan Y, Greenberg H, et al "Increased risk of death and cardiac arrest from encainide and flecainide in patients after non-Q-wave acute myocardial infarction in the cardiac arrhythmia suppressi." Am J Cardiol 68 (1991): 1551-5

4. Van Gelder IC, Crijns JGM, Van Gilst WH, et al "Efficacy and safety of flecainide acetate in the maintenance of sinus rhythm after electrical cardioversion of chronic atrial fibrillation or atrial flutter." Am J Cardiol 64 (1989): 1317-21

5. Forbes WP, Hee TT, Mohiuddin SM, Hillman DE "Flecainide-induced cardiogenic shock." Chest 94 (1988): 1121

6. Heisler BE, Ferrier GR "Proarrhythmic actions of flecainide in an isolated tissue model of ischemia and reperfusion." J Pharmacol Exp Ther 279 (1996): 317-24

7. Hopson JR, Buxton AE, Rinkenberger RL, Nademanee K, Heilman JM, Kienzle MG "Safety and utility of flecainide acetate in the routine care of patients with supraventricular tachyarrhythmias: results of a multicenter trial." Am J Cardiol 77 (1996): a72-82

8. Epstein AE, Hallstrom AP, Rogers WJ, Liebson PR, Seals AA, Anderson JL, Cohen JD, Capone RJ, Wyse DG "Mortality following ventricular arrhythmia suppression by encainide, flecainide, and moricizine after myocardial infarction - the original design concept of the cardiac arrhythmia suppression trial (cast)." JAMA 270 (1993): 2451-5

9. Puech P, Gagnol JP "Class IC drugs: propafenone and flecainide." Cardiovasc Drugs Ther 4 (1990): 549-53

10. Anderson JL, Platt ML, Guarnieri T, Fox TL, Maser MJ, Pritchett ELC, Kay GN, Plumb VJ, Epstein AE, Bubien RS, Bhandari "Flecainide acetate far paroxysmal supraventricular tachyarrhythmias." Am J Cardiol 74 (1994): 578-84

11. Levine B, Chute D, Caplan YH "Flecainide intoxication." J Anal Toxicol 14 (1990): 335-6

12. Winkelmann BR, Leinberger H "Life-threatening flecainide toxicity." Ann Intern Med 106 (1987): 807-14

13. Andrivet P, Beaslay V, Canh VD "Torsades de pointe with flecainide-amiodarone therapy." Intensive Care Med 16 (1990): 342-3

14. Fish FA, Gillette PC, Benson DW "Proarrhythmia, cardiac arrest and death in young patients receiving encainide and flecainide." J Am Coll Cardiol 18 (1991): 356-65

15. Karl M "Life-threatening flecainide toxicity." Ann Intern Med 107 (1987): 780

16. Hohnloser SH, Zabel M "Short- and long-term efficacy and safety of flecainide acetate for supraventricular arrhythmias." Am J Cardiol 70 (1992): a3-10

17. Said SAM, Somer ST, Luttikhuis HAO "Flecainide-induced JT prolongation, t wave inversion and ventricular tachycardia during treatment for symptomatic atrial fibrillation." Int J Cardiol 44 (1994): 285-7

18. Strambabadiale M, Lazzarotti M, Facchini M, Schwartz PJ "Malignant arrhythmias and acute myocardial ischemia: interaction between flecainide and the autonomic nervous system." Am Heart J 128 (1994): 973-82

19. Marcus FI "The hazards of using type 1C antiarrhythmic drugs for the treatment of paroxysmal atrial fibrillation." Am J Cardiol 66 (1990): 366-7

20. Roden DM "Risks and benefits of antiarrhythmic therapy." N Engl J Med 331 (1994): 785-91

21. Psaty BM, Psaty SE "Flecainide toxicity in an older adult." J Am Geriatr Soc 57 (2009): 751-3

22. Van Aubel KJJCM, Ruiter JH, Arnold AER, Burgersduk C "Pseudo infarction ECG pattern occurring during intravenous treatment with flecainide acetate." Eur Heart J 13 (1992): 137-9

23. Chimienti M, Cullen MT, Casadei G "Safety of long-term flecainide and propafenone in the management of patients with symptomatic paroxysmal atrial fibrillation: report from the flecainide and propafenone italian study investigators." Am J Cardiol 77 (1996): a60-5

24. Donovan KD, Power BM, Hockings BEF, Dobb G, Lee KY "Intravenous flecainide versus amiodarone for recent-onset atrial fibrillation." Am J Cardiol 75 (1995): 693-7

25. Anderson JL "Long-term safety and efficacy of flecainide in the treatment of supraventricular tachyarrhythmias: the united states experience." Am J Cardiol 70 (1992): a11-8

26. Aliot E, Denjoy I, Attuel, Admant, Rey, Janody, Richard, Lang, Valere, Morane, Kahn, Kayanakis, Janinmagnificat, Fauvel "Comparison of the safety and efficacy of flecainide versus propafenone in hospital out-patients with symptomatic paroxysmal atrial fibrillation/flutter." Am J Cardiol 77 (1996): a66-71

27. Salerno DM, Granrud G, Sharkey P, Krejci J, Larson T, Erlien D, Berry D, Hodges M "Pharmacodynamics and side effects of flecainide acetate." Clin Pharmacol Ther 40 (1986): 101-7

28. Windle JR, Witt RC, Rozanski GJ "Effects of flecainide on ectopic atrial automaticity and conduction." Circulation 88 (1993): 1878-84

29. Clementy J, Dulhoste MN, Laiter C, et al "Flecainide acetate in the prevention of paroxysmal atrial fibrillation: a nine-month follow-up of more than 500 patients." Am J Cardiol 70 (1992): a44-9

30. Crozier I "Flecainide in the wolff-parkinson-white syndrome." Am J Cardiol 70 (1992): a26-32

31. Facchini M, Varisco T, Bonazzi O, et al "Efficacy and safety of flecainide in low-risk patients with chronic ventricular arrhythmias: a two-year follow-up." Am Heart J 117 (1989): 1258-64

32. Cockrell JL, Scheinman MM, Titus C, et al "Safety and efficacy of oral flecainide therapy in patients with atrioventricular re-entrant tachycardia." Ann Intern Med 114 (1991): 189-94

33. Malesker MA, Sojka SG, Fagan NL "Flecainide-induced neuropathy." Ann Pharmacother 39 (2005): 1580-1

34. Pedersen KE, Christiansen BD, Kjaer K, Klitgaard NA, Nielsen-Kudsk F "Verapamil-induced changes in digoxin kinetics and intraerythrocytic sodium concentration." Clin Pharmacol Ther 34 (1983): 8-13

35. Moller HU, Thygesen K, Kruit PJ "Corneal deposits associated with flecainide." BMJ 302 (1991): 506-7

36. Hellestrand KJ "Efficacy and safety of long-term oral flecainide acetate in patients with responsive supraventricular tachycardia." Am J Cardiol 77 (1996): a83-8

37. Ferrick KJ, Power M "Profound exacerbation of neuromuscular weakness by flecainide." Am Heart J 119 (1990): 414-5

38. Ramhamadany E, Mackenzie S, Ramsdale DR "Dysarthria and visual hallucinations due to flecainide toxicity." Postgrad Med J 62 (1986): 61-2

39. Ziegelbaum M, Lever H "Acute urinary retention associated with flecainide." Cleve Clin J Med 57 (1990): 86-7

40. Akoun GM, Cadranel JL, Israel-Biet D, Gauthier-Rahman S "Flecainide-associated pneumonitis." Lancet 337 (1991): 49

41. "Product Information. Tambocor (flecainide)." 3M Pharmaceuticals, St. Paul, MN.

42. Bennett MI "Paranoid psychosis due to flecainide toxicity in malignant neuropathic pain." Pain 70 (1997): 93-4

Disclaimer: Every effort has been made to ensure that the information provided is accurate, up-to-date and complete, but no guarantee is made to that effect. In addition, the drug information contained herein may be time sensitive and should not be utilized as a reference resource beyond the date hereof. This material does not endorse drugs, diagnose patients, or recommend therapy. This information is a reference resource designed as supplement to, and not a substitute for, the expertise, skill , knowledge, and judgement of healthcare practitioners in patient care. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate safety, effectiveness, or appropriateness for any given patient. Drugs.com does not assume any responsibility for any aspect of healthcare administered with the aid of materials provided. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the substances you are taking, check with your doctor, nurse, or pharmacist.

Hide
(web3)