Prescription medication · Class IC Antiarrhythmic

propafenone

Also sold as Rythmol. This medicine is used to help keep your heart rhythm normal if you have atrial fibrillation or supraventricular tachycardia.

Data updated 2026-05-15

4,113
FDA reportsLightly reported
26
InteractionsSeveral interactions
In shortage
FDA status

What the data shows

propafenone (Rythmol) is a prescription Class IC Antiarrhythmic, among the least-reported drugs the FDA tracks (4,113 FDA reports), with 26 documented drug interactions.

Reporting volume reflects how widely a drug is used and studied, not how dangerous it is, a FAERS report documents a temporal association, never proof of cause.

propafenone (Rythmol) is a prescription Class IC Antiarrhythmic. This medicine is used to help keep your heart rhythm normal if you have atrial fibrillation or supraventricular tachycardia.

Propafenone (Rythmol) is a medicine that helps control irregular heartbeats. It works by slowing down electrical signals in the heart.

Drug Shortage Alert

propafenone is currently listed as to be discontinued by the FDA. Affected manufacturer: Upsher-Smith Laboratories, LLC.

View all drug shortages →

Drug Pricing (NADAC)

Generic Price

$0.12/unit

Generic Available

Yes (11 manufacturers)

Pricing data from NADAC (CMS), effective December 18, 2024. Compare all drug costs →

NADAC price trail: PROPAFENONE HCL 150 MG TABLET

Same CMS presentation as the headline generic unit price above (2 effective dates). Adjacent % compares consecutive NADAC releases for this description only, not a patient out-of-pocket quote. Latest step: -16.1% vs prior release.

Effective NADAC / unit vs prior NDCs
February 21, 2024 $0.1384/EA - 3
December 18, 2024 $0.1162/EA -16.1% 7
View Alternatives → Compare with Another Drug → Full Side Effects Report →

What it does

This medicine is used to help keep your heart rhythm normal if you have atrial fibrillation or supraventricular tachycardia.

Common side effects

Unusual taste, Nausea, Vomiting

Key warnings

This medicine may increase the risk of death in people with heart problems.

The sections below are summarized in plain English from propafenone's FDA-approved prescribing information. They describe what the official label says, and are not personal medical advice.

How It Works

Propafenone works by affecting the electrical activity in your heart. It slows down the signals that cause irregular heartbeats. This helps your heart beat more regularly.

Side Effects (from patient reports)

Based on 4,113 FDA adverse event reports.

Most-reported reactions

Adverse reactions in FAERS for propafenone, by number of reports

reports

What this shows Bars show how often each reaction was reported, not how likely it is to happen, a report records a temporal association, never proof that the drug caused it.

Source FDA Adverse Event Reporting System (FAERS) As of 2025

Reports over time

Adverse-event reports filed for propafenone each year to the FDA Adverse Event Reporting System (FAERS).

0100200300400500 20042007201020132016201920222025 218

Year-to-year volume tracks usage, prescribing, and scrutiny, not a change in per-patient risk. Source: FDA FAERS.

Where propafenone sits

propafenone has more FDA adverse-event reports than 23% of the drugs FAERS tracks. A high position reflects how widely a drug is used and watched, not how dangerous it is.

fewest reports most reports

Percentile across all drugs PlainMeds tracks by FAERS report volume. The dot is propafenone; the line is the median (50th percentile).

FDA Adverse Event Report Analysis

Detailed analysis of 4,113 reports from the FDA Adverse Event Reporting System (FAERS). Reports span 2004–2025.

Total Reports

4,113

Reports Mentioning Death

483

11.7% of reports — not proof of cause

Hospitalization Reports

1,763

Top Indication

Product Used For Unknown Indication

Gender Distribution

Female 2,197 (58%)
Male 1,568 (41%)

Age Distribution

0–17 104
18–44 214
45–64 764
65–74 1,001
75+ 1,019

Most Reported Adverse Reactions (FAERS)

# Reaction Reports
1 ATRIAL FIBRILLATION 347
3 DRUG INTERACTION 320
4 DIZZINESS 262
5 TOXICITY TO VARIOUS AGENTS 231
6 DYSPNOEA 226
7 NAUSEA 206
8 FATIGUE 201
10 ASTHENIA 181
11 BRADYCARDIA 168
12 HYPOTENSION 164
13 DIARRHOEA 143
14 FALL 142
15 ARRHYTHMIA 137
16 CARDIAC ARREST 127
17 ELECTROCARDIOGRAM QRS COMPLEX PROLONGED 125

Reactions in Death Reports

COMPLETED SUICIDE 114
DEATH 87
TOXICITY TO VARIOUS AGENTS 61
DRUG INTERACTION 46
CARDIAC ARREST 40
ACUTE KIDNEY INJURY 32
SUBARACHNOID HAEMORRHAGE 29
ELECTROCARDIOGRAM QRS COMPLEX PROLONGED 27
LOSS OF CONSCIOUSNESS 26
HYPOTENSION 25

Reactions in Hospitalization Reports

ATRIAL FIBRILLATION 194
DRUG INTERACTION 158
TOXICITY TO VARIOUS AGENTS 151
DYSPNOEA 124
NAUSEA 109
BRADYCARDIA 108
DIZZINESS 107
ASTHENIA 105
HYPOTENSION 102
ACUTE KIDNEY INJURY 87

Source: FDA FAERS (Adverse Event Reporting System) Reports are voluntary and do not establish causation

Serious Warnings

This medicine may increase the risk of death in people with heart problems. Do not take this medicine if you have structural heart disease and non-life-threatening ventricular arrhythmias. Talk to your doctor about the risks and benefits of taking this medicine.

Known Drug Interactions

Antiarrhythmics amiodarone, dronedarone, flecainide, propafenone, quinidine ↑ antiarrhythmic Co-administration contraindicated due to potential for cardiac arrhythmias [see Contraindications (4) ] .

Mechanism: Taking these together causes propafenone to stay in your body longer and reach higher levels than intended. This can lead to serious and potentially fatal heart rhythm disturbances.

moderate amiodarone

Amiodarone Concomitant administration of propafenone and amiodarone can affect conduction and repolarization and is not recommended.

Mechanism: Taking these two heart medicines together can change how electrical signals travel through your heart. This can interfere with your heart's rhythm and how it resets between beats.

moderate fluoxetine

Coadministration of fluoxetine with other drugs that are metabolized by CYP2D6, including certain antidepressants (e.g., TCAs), antipsychotics (e.g., phenothiazines and most atypicals), and antiarrhythmics (e.g., propafenone, flecainide, and others) should be approached with caution. Drugs with a narrow therapeutic index represent the greatest concern (e.g., flecainide, propafenone, vinblastine, and TCAs).

Mechanism: Fluoxetine slows down how fast your body processes propafenone. This can lead to higher amounts of the heart medicine in your system than intended.

moderate nebivolol

( 7.4 ) 7.1 CYP2D6 Inhibitors Use caution when nebivolol is co-administered with CYP2D6 inhibitors (quinidine, propafenone, fluoxetine, paroxetine, etc.) [ see Clinical Pharmacology ( 12.5 ) ].

Mechanism: Propafenone slows down the body's ability to process nebivolol, which could cause the medication to build up to higher levels.

(7.6) 7.1 CYP2D6 and CYP3A4 Inhibitors Drugs that inhibit CYP2D6 (such as desipramine, paroxetine, ritonavir, sertraline) and CYP3A4 (such as ketoconazole, ritonavir, saquinavir, erythromycin, grapefruit juice) can be expected to cause increased plasma levels of propafenone.

Mechanism: Ketoconazole slows down the liver's ability to break down propafenone, which can cause the drug to build up in your body.

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This is a plain-language summary of FDA-label interaction records and does not provide individual medication-combination directions.

Common Questions

Can I take this medicine if I have heart failure?
No, you should not take this medicine if you have heart failure.
Can I take this medicine if I have a pacemaker?
This medicine may affect artificial pacemakers. Your doctor will monitor your pacemaker function.
What should I do if I feel dizzy after taking this medicine?
Dizziness is a common side effect. If you feel dizzy, sit or lie down until the feeling passes.
Can I drink grapefruit juice while taking this medicine?
No, avoid grapefruit juice while taking this medicine. It can increase the level of propafenone in your blood.
What if I develop an infection while taking this medicine?
Tell your doctor right away if you develop signs of infection, such as fever, sore throat, or chills.
Can this medicine worsen my myasthenia gravis?
Yes, this medicine may make myasthenia gravis worse.
Can I take this with other heart medicines?
Tell your doctor about all the medicines you take, including heart medicines, before starting propafenone.
What if my heart rhythm gets worse on this medicine?
This medicine can sometimes cause new or worsened arrhythmias. Your doctor will monitor you with ECGs.
Can this medicine affect my blood pressure?
This medicine can cause low blood pressure. Tell your doctor if you feel lightheaded or dizzy.
Is it safe to take propafenone while breastfeeding?
Talk to your doctor about the risks and benefits of taking propafenone while breastfeeding.
What are the common side effects of propafenone?
The registry lists Unusual taste, Nausea, Vomiting, Dizziness, Constipation among the most-reported FAERS reaction terms for propafenone. The compiled record contains 4,113 FDA adverse-event reports. These counts are not an individual symptom assessment.
Does propafenone interact with other medications?
The registry has 26 documented interaction rows for propafenone. Notable source-record pairings include nirmatrelvir/ritonavir, amiodarone, fluoxetine. These rows are not a complete medication review.
What drug class is propafenone?
propafenone belongs to the Class IC Antiarrhythmic drug class. It requires a prescription (Rx). This medicine is used to help keep your heart rhythm normal if you have atrial fibrillation or supraventricular tachycardia.
What pregnancy or breastfeeding source fields are listed for propafenone?
The FDA label for propafenone contains product-specific pregnancy or breastfeeding language. PlainMeds does not apply that source text to an individual.
Has propafenone been recalled?
There is 1 recall associated with propafenone products. CGMP Deviations. Check the recalls section below for full details and affected products.
Is propafenone currently in shortage?
Yes, propafenone is currently listed as to be discontinued by the FDA. Affected manufacturer: Upsher-Smith Laboratories, LLC. Visit the FDA Drug Shortages database for the latest updates.

Active Recalls

Class II March 13, 2025

CGMP Deviations

Glenmark Pharmaceuticals Inc., USA

Other drugs grouped near propafenone - same-class peers and common alternatives.

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Compare beyond drug class

Nationwide peers by FAERS volume & death-report share

Two PlainMeds-derived comparison paths for propafenone: nearest FDA FAERS report volume and nearest death-report share among drugs with at least 1,000 logged reports, excluding same-class neighbors listed above. Counts reflect reporting volume, not proven individual harm.

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What the FDA Data Shows for propafenone

The FDA label for propafenone (sold under brand names such as Rythmol) classifies it as a prescription-only medication in the Class IC Antiarrhythmic class. This medicine is used to help keep your heart rhythm normal if you have atrial fibrillation or supraventricular tachycardia. Official labeling lists 9 commonly reported side effects, including Unusual taste, Nausea, Vomiting.

Post-market surveillance from the FDA Adverse Event Reporting System (FAERS) captures real-world experience. For this drug, FAERS contains 4,113 voluntary reports. The database also lists 26 documented drug interactions derived from FDA labeling, with the top-flagged interaction rated major severity. NADAC pricing from CMS shows a generic unit cost of $0.12.

Report counts do not establish causation, a FAERS entry documents a temporal association, not proof that the drug produced the outcome. Widely prescribed medications naturally accumulate more reports than niche therapies, so raw totals must be interpreted alongside total exposure. Shortage status, recall history (currently 1 recall record on file), and patent information are separate source-record fields. This page is a public FDA/CMS registry and does not provide medical, treatment, substitution, or medication-change directions.

Data Sources

Drug labeling: FDA Drug Labels (SPL/DailyMed). Adverse events: FDA Adverse Event Reporting System (FAERS). Pricing: CMS National Average Drug Acquisition Cost (NADAC). Shortage status: FDA Drug Shortages Database.

FAERS reports are voluntary and do not establish causation. Drug interactions are derived from FDA labeling and clinical references. This registry does not provide medication decisions.

Last updated: July 21, 2023

PlainMeds is rendered directly from FDA openFDA/FAERS extracts, DailyMed labels, and CMS drug-pricing files, no number is typed in by an editor. FAERS counts, recalls, shortages, and price figures on this page are queried live from those federal extracts. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of 2026-05-15. Primary sources: openFDA / FAERS, DailyMed and CMS Part B ASP.

Data currency: FDA FAERS adverse-event reports through 2025, CMS NADAC acquisition-cost pricing effective December 2024, compiled from the source snapshot dated . See our methodology for per-source dates and refresh cadence. Spot a figure that looks wrong? Report a data issue.

All federal data sources used on this page