FDA label e271f15f-9dfd-8e72-e053-2a95a90ab2a2

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Boxed warning cross-check#

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boxed warning

WARNING: MORTALITY In the National Heart, Lung, and Blood Institute’s Cardiac Arrhythmia Suppression Trial (CAST), a long-term, multicenter, randomized, double-blind trial in subjects with asymptomatic non-life-threatening ventricular arrhythmias who had a myocardial infarction more than 6 days but less than 2 years previously, an increased rate of death or reversed cardiac arrest rate (7.7%; 56/730) was seen in subjects treated with encainide or flecainide (Class IC antiarrhythmics) compared with that seen in subjects assigned to placebo (3.0%; 22/725). The average duration of treatment with encainide or flecainide in this trial was 10 months. The applicability of the CAST results to other populations (e.g., those without recent myocardial infarction) or other antiarrhythmic drugs is uncertain, but at present, it is prudent to consider any IC antiarrhythmic to have a significant proarrhythmic risk in patients with structural heart disease. Given the lack of any evidence that these drugs improve survival, antiarrhythmic agents should generally be avoided in patients with non-life-threatening ventricular arrhythmias, even if the patients are experiencing unpleasant, but not life-threatening, symptoms or signs. WARNING: MORTALITY See full prescribing information for complete boxed warning. An increased rate of death or reversed cardiac arrest rate was seen in subjects treated with encainide or flecainide (Class IC antiarrhythmics) compared with that seen in subjects assigned to placebo. At present, it is prudent to consider any IC antiarrhythmic to have a significant risk of provoking proarrhythmic events in patients with structural heart disease. Given the lack of any evidence that these drugs improve survival, antiarrhythmic agents should generally be avoided in patients with non-life-threatening ventricular arrhythmias, even if the patients are experiencing unpleasant, but not life-threatening, symptoms or signs.

Warnings cross-check#

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warnings and cautions

5 WARNINGS AND PRECAUTIONS May cause new or worsened arrhythmias. Evaluate patients via ECG prior to and during therapy. ( 5.1 ) Propafenone hydrochloride may unmask Brugada or Brugada-like Syndrome. ( 4 , 5.2 ) Avoid use with other drugs that prolong the QT interval. ( 5.3 ) Avoid simultaneous use of propafenone with both a cytochrome P450 2D6 (CYP2D6) inhibitor and a 3A4 (CYP3A4) inhibitor. ( 5.4 ) May provoke overt heart failure. ( 5.5 ) May cause dose-related first-degree AV block or other conduction disturbances. Only use in patients with conduction disorders who have pacemakers. ( 5.6 ) May affect artificial pacemakers. Monitor pacemaker function. ( 5.7 ) Agranulocytosis: Patients should report signs of infection. ( 5.8 ) May exacerbate myasthenia gravis. ( 5.11 ) 5.1 Proarrhythmic Effects Propafenone has caused new or worsened arrhythmias. Such proarrhythmic effects include sudden death and life-threatening ventricular arrhythmias such as ventricular fibrillation, ventricular tachycardia, asystole and torsade de pointes. It may also worsen premature ventricular contractions or supraventricular arrhythmias, and it may prolong the QT interval. It is therefore essential that each patient given propafenone hydrochloride be evaluated electrocardiographically prior to and during therapy to determine whether the response to propafenone hydrochloride supports continued treatment. Because propafenone prolongs the QRS interval in the electrocardiogram, changes in the QT interval are difficult to interpret [see Clinical Pharmacology (12.2) ]. In a U.S. uncontrolled, open label, multicenter trial in subjects with symptomatic supraventricular tachycardia (SVT), 1.9% (9/474) of these subjects experienced ventricular tachycardia (VT) or ventricular fibrillation (VF) during the trial. However, in 4 of the 9 subjects, the ventricular tachycardia was of atrial origin. Six of the nine subjects that developed ventricular arrhythmias did so within 14 days of onset of therapy. About 2.3% (11/474) of all subjects had a recurrence of SVT during the trial which could have been a change in the subjects’ arrhythmia behavior or could represent a proarrhythmic event. Case reports in patients treated with propafenone for atrial fibrillation/flutter have included increased premature ventricular contractions (PVCs), VT, VF, torsade de pointes, asystole, and death. Overall in clinical trials with propafenone hydrochloride (which included subjects treated for ventricular arrhythmias, atrial fibrillation/flutter, and PSVT), 4.7% of all subjects had new or worsened ventricular arrhythmia possibly representing a proarrhythmic event (0.7% was an increase in PVCs; 4.0% a worsening, or new appearance of VT or VF). Of the subjects who had worsening of VT (4%), 92% had a history of VT and/or VT/VF, 71% had coronary artery disease, and 68% had a prior myocardial infarction. The incidence of proarrhythmia in subjects with less serious or benign arrhythmias, which include subjects with an increase in frequency of PVCs, was 1.6%. Although most proarrhythmic events occurred during the first week of therapy, late events also were seen and the CAST trial [see Boxed Warning: Mortality ] suggests that an increased risk of proarrythmia is present throughout treatment. In a trial of sustained-release propafenone, there were too few deaths to assess the long-term risk to patients. There were 5 deaths; 3 in the pooled group for sustained-release propafenone (0.8%) and 2 in the placebo group (1.6%). In the overall database of 8 trials of sustained-release propafenone and immediate-release propafenone hydrochloride, the mortality rate was 2.5% per year on propafenone and 4.0% per year on placebo. Concurrent use of propafenone with other antiarrhythmic agents has not been well studied. 5.2 Unmasking Brugada Syndrome Brugada Syndrome may be unmasked after exposure to propafenone hydrochloride. Perform an ECG after initiation of propafenone hydrochloride, and discontinue the drug if changes are suggestive of Brugada Syndrome [see Contraindications (4) ]. 5.3 Use with Drugs that Prolong the QT Interval and Antiarrhythmic Agents The use of propafenone hydrochloride in conjunction with other drugs that prolong the QT interval has not been extensively studied. Such drugs may include many antiarrhythmics, some phenothiazines, tricyclic antidepressants, and oral macrolides. Withhold Class IA and III antiarrhythmic agents for at least 5 half-lives prior to dosing with propafenone hydrochloride. Avoid the use of propafenone with Class IA and III antiarrhythmic agents (including quinidine and amiodarone). There is only limited experience with the concomitant use of Class IB or IC antiarrhythmics. 5.4 Drug Interactions: Simultaneous Use with Inhibitors of Cytochrome P450 Isoenzymes 2D6 and 3A4 Propafenone is metabolized by CYP2D6, CYP3A4, and CYP1A2 isoenzymes. Approximately 6% of Caucasians in the U.S. population are naturally deficient in CYP2D6 activity and other demographic groups are deficient to a somewhat lesser extent. Drugs that inhibit these CYP pathways (such as desipramine, paroxetine, ritonavir, sertraline for CYP2D6; ketoconazole, erythromycin, saquinavir, and grapefruit juice for CYP3A4; and amiodarone and tobacco smoke for CYP1A2) can be expected to cause increased plasma levels of propafenone. Increased exposure to propafenone may lead to cardiac arrhythmias and exaggerated beta-adrenergic blocking activity. Because of its metabolism, the combination of CYP3A4 inhibition and either CYP2D6 deficiency or CYP2D6 inhibition in users of propafenone is potentially hazardous. Therefore, avoid simultaneous use of propafenone hydrochloride with both a CYP2D6 inhibitor and a CYP3A4 inhibitor. 5.5 Use in Patients with a History of Heart Failure Propafenone exerts a negative inotropic activity on the myocardium as well as beta-blockade effects and may provoke overt heart failure. In clinical trial experience with propafenone hydrochloride, new or worsened congestive heart failure (CHF) has been reported in 3.7% of subjects with ventricular arrhythmia; of those 0.9% were considered probably or definitely related to propafenone HCl. Of the subjects with CHF probably related to propafenone, 80% had preexisting heart failure and 85% had coronary artery disease. CHF attributable to propafenone HCl developed rarely (less than 0.2%) in subjects with ventricular arrhythmia who had no previous history of CHF. CHF occurred in 1.9% of subjects studied with PAF or PSVT. In a U.S. trial of sustained-release propafenone in subjects with symptomatic AF, heart failure was reported in 4 (1.0%) subjects receiving sustained-release propafenone (all doses), compared with 1 (0.8%) subject receiving placebo. 5.6 Conduction Disturbances Propafenone slows atrioventricular conduction and may also cause dose-related first degree AV block. Average PR interval prolongation and increases in QRS duration are also dose-related. Do not give propafenone to patients with atrioventricular and intraventricular conduction defects in the absence of a pacemaker [see Contraindications (4) and Clinical Pharmacology (12.2) ]. The incidence of first-degree, second-degree, and third-degree AV block observed in 2,127 subjects with ventricular arrhythmia was 2.5%, 0.6%, and 0.2%, respectively. Development of second- or third-degree AV block requires a reduction in dosage or discontinuation of propafenone HCl. Bundle branch block (1.2%) and intraventricular conduction delay (1.1%) have been reported in subjects receiving propafenone. Bradycardia has also been reported (1.5%). Experience in patients with sick sinus node syndrome is limited and these patients should not be treated with propafenone. In a U.S. trial in 523 subjects with a history of symptomatic AF treated with sustained-release propafenone, sinus bradycardia (rate less than 50 beats/min) was reported with the same frequency with sustained-release propafenone and placebo. 5.7 Effects on Pacemaker Threshold Propafenone may alter both pacing and sensing thresholds of implanted pacemakers and defibrillators. During and after therapy, monitor and re-program these devices accordingly. 5.8 Agranulocytosis Agranulocytosis has been reported in patients receiving propafenone. Generally, the agranulocytosis occurred within the first 2 months of propafenone therapy and upon discontinuation of therapy the white count usually normalized by 14 days. Unexplained fever or decrease in white cell count, particularly during the initial 3 months of therapy, warrant consideration of possible agranulocytosis or granulocytopenia. Instruct patients to report promptly any signs of infection such as fever, sore throat, or chills. 5.9 Use in Patients with Hepatic Dysfunction Propafenone is highly metabolized by the liver. Severe liver dysfunction increases the bioavailability of propafenone to approximately 70% compared with 3% to 40% in patients with normal liver function. In 8 subjects with moderate to severe liver disease, the mean half-life was approximately 9 hours. Increased bioavailability of propafenone in these patients may result in excessive accumulation. Carefully monitor patients with impaired hepatic function for excessive pharmacological effects [see Overdosage (10) ]. 5.10 Use in Patients with Renal Dysfunction Approximately 50% of propafenone metabolites are excreted in the urine following administration of propafenone hydrochloride. In patients with impaired renal function, monitor for signs of overdosage [see Overdosage (10) ]. 5.11 Use in Patients with Myasthenia Gravis Exacerbation of myasthenia gravis has been reported during propafenone therapy. 5.12 Elevated ANA Titers Positive ANA titers have been reported in patients receiving propafenone. They have been reversible upon cessation of treatment and may disappear even in the face of continued propafenone therapy. These laboratory findings were usually not associated with clinical symptoms, but there is one published case of drug-induced lupus erythematosus (positive rechallenge); it resolved completely upon discontinuation of therapy. Carefully evaluate patients who develop an abnormal ANA test and, if persistent or worsening elevation of ANA titers is detected, consider discontinuing therapy.

Adverse reactions cross-check#

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adverse reactions

6 ADVERSE REACTIONS The most commonly reported adverse events with propafenone (greater than 5%) included: unusual taste, nausea and/or vomiting, dizziness, constipation, headache, fatigue, first-degree AV block, and intraventricular conduction delay. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Par Pharmaceutical at 1-800-828-9393 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch . 6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared with rates in the clinical trials of another drug and may not reflect the rates observed in practice. Adverse reactions associated with propafenone hydrochloride occur most frequently in the gastrointestinal, cardiovascular, and central nervous systems. About 20% of subjects treated with propafenone hydrochloride have discontinued treatment because of adverse reactions. Adverse reactions reported for greater than 1.5% of 474 subjects with SVT who received propafenone hydrochloride in U.S. clinical trials are presented in Table 1 by incidence and percent discontinuation, reported to the nearest percent. Table 1: Adverse Reactions Reported for > 1.5% of Subjects with Supraventricular Tachycardia Adverse Reaction Incidence (N = 480) % of Subjects Who Discontinued Unusual Taste 14% 1.3% Nausea and/or Vomiting 11% 2.9% Dizziness 9% 1.7% Constipation 8% 0.2% Headache 6% 0.8% Fatigue 6% 1.5% Blurred Vision 3% 0.6% Weakness 3% 1.3% Dyspnea 2% 1.0% Wide Complex Tachycardia 2% 1.9% CHF 2% 0.6% Bradycardia 2% 0.2% Palpitations 2% 0.2% Tremor 2% 0.4% Anorexia 2% 0.2% Diarrhea 2% 0.4% Ataxia 2% 0.0% In controlled trials in subjects with ventricular arrhythmia, the most common reactions reported for propafenone hydrochloride and more frequent than on placebo were unusual taste, dizziness, first-degree AV block, intraventricular conduction delay, nausea and/or vomiting, and constipation. Headache was relatively common also, but was not increased compared with placebo. Other reactions reported more frequently than on placebo or comparator and not already reported elsewhere included anxiety, angina, second-degree AV block, bundle branch block, loss of balance, congestive heart failure, and dyspepsia. Adverse reactions reported for greater than or equal to 1% of 2,127 subjects with ventricular arrhythmia who received propafenone in U.S. clinical trials were evaluated by daily dose. The most common adverse reactions appeared dose-related (but note that most subjects spent more time at the larger doses), especially dizziness, nausea and/or vomiting, unusual taste, constipation, and blurred vision. Some less common reactions may also have been dose-related such as first degree AV block, congestive heart failure, dyspepsia, and weakness. Other adverse reactions included rash, syncope, chest pain, abdominal pain, ataxia, and hypotension. In addition, the following adverse reactions were reported less frequently than 1% either in clinical trials or in marketing experience. Causality and relationship to propafenone therapy cannot necessarily be judged from these events. Cardiovascular System: Atrial flutter, AV dissociation, cardiac arrest, flushing, hot flashes, sick sinus syndrome, sinus pause or arrest, supraventricular tachycardia. Nervous System: Abnormal dreams, abnormal speech, abnormal vision, confusion, depression, memory loss, numbness, paresthesias, psychosis/mania, seizures (0.3%), tinnitus, unusual smell sensation, vertigo. Gastrointestinal: Cholestasis, elevated liver enzymes (alkaline phosphatase, serum transaminases), gastroenteritis, hepatitis. Hematologic: Agranulocytosis, anemia, bruising, granulocytopenia, leukopenia, purpura, thrombocytopenia. Other: Alopecia, eye irritation, impotence, increased glucose, positive ANA (0.7%), muscle cramps, muscle weakness, nephrotic syndrome, pain, pruritus. 6.2 Postmarketing Experience The following adverse reactions have been identified during post-approval use of propafenone hydrochloride. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure. Gastrointestinal: A number of patients with liver abnormalities associated with propafenone therapy have been reported in post-marketing experience. Some appeared due to hepatocellular injury, some were cholestatic and some showed a mixed picture. Some of these reports were simply discovered through clinical chemistries, others because of clinical symptoms including fulminant hepatitis and death. One case was rechallenged with a positive outcome. Blood and Lymphatic System: Increased bleeding time Immune System: lupus erythematosus Nervous System: Apnea, coma Renal and Urinary: Hyponatremia/inappropriate ADH secretion, kidney failure

adverse reactions table

<table width="100%" ID="_RefID0EI4AE"><caption>Table 1: Adverse Reactions Reported for &gt; 1.5% of Subjects with Supraventricular Tachycardia</caption><colgroup><col width="33%"/><col width="33%"/><col width="34%"/></colgroup><tbody><tr><td styleCode="Rrule Lrule Toprule " valign="middle"><paragraph><content styleCode="bold">Adverse Reaction</content></paragraph></td><td align="center" styleCode="Rrule Lrule Toprule " valign="middle"><paragraph><content styleCode="bold">Incidence</content> <content styleCode="bold">(N = 480)</content></paragraph></td><td align="center" styleCode="Rrule Lrule Toprule " valign="middle"><paragraph><content styleCode="bold">% of Subjects Who Discontinued </content></paragraph></td></tr><tr><td styleCode="Rrule Lrule Botrule " valign="middle"><paragraph>Unusual Taste</paragraph></td><td align="center" styleCode="Rrule Lrule Botrule " valign="middle"><paragraph>14%</paragraph></td><td align="center" styleCode="Rrule Lrule Botrule " valign="middle"><paragraph>1.3%</paragraph></td></tr><tr><td styleCode="Rrule Lrule Botrule " valign="middle"><paragraph>Nausea and/or Vomiting</paragraph></td><td align="center" styleCode="Rrule Lrule Botrule " valign="middle"><paragraph>11%</paragraph></td><td align="center" styleCode="Rrule Lrule Botrule " valign="middle"><paragraph>2.9%</paragraph></td></tr><tr><td styleCode="Rrule Lrule Botrule " valign="middle"><paragraph>Dizziness</paragraph></td><td align="center" styleCode="Rrule Lrule Botrule " valign="middle"><paragraph>9%</paragraph></td><td align="center" styleCode="Rrule Lrule Botrule " valign="middle"><paragraph>1.7%</paragraph></td></tr><tr><td styleCode="Rrule Lrule Botrule " valign="middle"><paragraph>Constipation</paragraph></td><td align="center" styleCode="Rrule Lrule Botrule " valign="middle"><paragraph>8%</paragraph></td><td align="center" styleCode="Rrule Lrule Botrule " valign="middle"><paragraph>0.2%</paragraph></td></tr><tr><td styleCode="Rrule Lrule Botrule " valign="middle"><paragraph>Headache</paragraph></td><td align="center" styleCode="Rrule Lrule Botrule " valign="middle"><paragraph>6%</paragraph></td><td align="center" styleCode="Rrule Lrule Botrule " valign="middle"><paragraph>0.8%</paragraph></td></tr><tr><td styleCode="Rrule Lrule Botrule " valign="middle"><paragraph>Fatigue</paragraph></td><td align="center" styleCode="Rrule Lrule Botrule " valign="middle"><paragraph>6%</paragraph></td><td align="center" styleCode="Rrule Lrule Botrule " valign="middle"><paragraph>1.5%</paragraph></td></tr><tr><td styleCode="Rrule Lrule Botrule " valign="middle"><paragraph>Blurred Vision</paragraph></td><td align="center" styleCode="Rrule Lrule Botrule " valign="middle"><paragraph>3%</paragraph></td><td align="center" styleCode="Rrule Lrule Botrule " valign="middle"><paragraph>0.6%</paragraph></td></tr><tr><td styleCode="Rrule Lrule Botrule " valign="middle"><paragraph>Weakness</paragraph></td><td align="center" styleCode="Rrule Lrule Botrule " valign="middle"><paragraph>3%</paragraph></td><td align="center" styleCode="Rrule Lrule Botrule " valign="middle"><paragraph>1.3%</paragraph></td></tr><tr><td styleCode="Rrule Lrule Botrule " valign="middle"><paragraph>Dyspnea</paragraph></td><td align="center" styleCode="Rrule Lrule Botrule " valign="middle"><paragraph>2%</paragraph></td><td align="center" styleCode="Rrule Lrule Botrule " valign="middle"><paragraph>1.0%</paragraph></td></tr><tr><td styleCode="Rrule Lrule Botrule " valign="middle"><paragraph>Wide Complex Tachycardia</paragraph></td><td align="center" styleCode="Rrule Lrule Botrule " valign="middle"><paragraph>2%</paragraph></td><td align="center" styleCode="Rrule Lrule Botrule " valign="middle"><paragraph>1.9%</paragraph></td></tr><tr><td styleCode="Rrule Lrule Botrule " valign="middle"><paragraph>CHF</paragraph></td><td align="center" styleCode="Rrule Lrule Botrule " valign="middle"><paragraph>2%</paragraph></td><td align="center" styleCode="Rrule Lrule Botrule " valign="middle"><paragraph>0.6%</paragraph></td></tr><tr><td styleCode="Rrule Lrule Botrule " valign="middle"><paragraph>Bradycardia</paragraph></td><td align="center" styleCode="Rrule Lrule Botrule " valign="middle"><paragraph>2%</paragraph></td><td align="center" styleCode="Rrule Lrule Botrule " valign="middle"><paragraph>0.2%</paragraph></td></tr><tr><td styleCode="Rrule Lrule Botrule " valign="middle"><paragraph>Palpitations</paragraph></td><td align="center" styleCode="Rrule Lrule Botrule " valign="middle"><paragraph>2%</paragraph></td><td align="center" styleCode="Rrule Lrule Botrule " valign="middle"><paragraph>0.2%</paragraph></td></tr><tr><td styleCode="Rrule Lrule Botrule " valign="middle"><paragraph>Tremor</paragraph></td><td align="center" styleCode="Rrule Lrule Botrule " valign="middle"><paragraph>2%</paragraph></td><td align="center" styleCode="Rrule Lrule Botrule " valign="middle"><paragraph>0.4%</paragraph></td></tr><tr><td styleCode="Rrule Lrule Botrule " valign="middle"><paragraph>Anorexia</paragraph></td><td align="center" styleCode="Rrule Lrule Botrule " valign="middle"><paragraph>2%</paragraph></td><td align="center" styleCode="Rrule Lrule Botrule " valign="middle"><paragraph>0.2%</paragraph></td></tr><tr><td styleCode="Rrule Lrule Botrule " valign="middle"><paragraph>Diarrhea</paragraph></td><td align="center" styleCode="Rrule Lrule Botrule " valign="middle"><paragraph>2%</paragraph></td><td align="center" styleCode="Rrule Lrule Botrule " valign="middle"><paragraph>0.4%</paragraph></td></tr><tr><td styleCode="Rrule Botrule Lrule " valign="middle"><paragraph>Ataxia</paragraph></td><td align="center" styleCode="Rrule Botrule Lrule " valign="middle"><paragraph>2%</paragraph></td><td align="center" styleCode="Rrule Botrule Lrule " valign="middle"><paragraph>0.0%</paragraph></td></tr></tbody></table>