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PROPAFENONE HYDROCHLORIDE 225 mg Capsule, Extended Release, 500-count — NDC 16571-0736-50 package photo

PROPAFENONE HYDROCHLORIDE 225 mg Capsule, Extended Release, 500-count

by Rising Pharma Holdings, Inc. · 500 CAPSULE, EXTENDED RELEASE in 1 BOTTLE (16571-736-50)
NDC 16571-0736-50
🏷️ FDA NDC (as labeled) 16571-736-50 billing pads the product segment with a zero
This package
Contains500-count Pack sizes2 compare ↓
Also priced by: Part D plans $0.9500/unit — full pricing hub ↓
Also comes in: 60 capsules 16571-0736-06
Rx only Generic On market Non-controlled
🗂️ Data synced Jul 24, 2026 · sources: openFDA · FDA label (DailyMed) · FDA Orange & Purple Book · First Databank · CMS NADAC, ASP, Medicare & Medicaid · RxNorm
📋 All sources & update times →

This page is curated, coded, and maintained by

Compiled from public FDA, CMS, DailyMed, NADAC, and related drug data sources. Editorial policy

⚠️
Other active recalls for Propafenone Hydrochloride (different manufacturers) — 4 · tap to view
These affect other manufacturers’ products for the same ingredient — not necessarily the exact NDC on this page.
Class II · Mar 13, 2025 — CGMP Deviations (Glenmark Pharmaceuticals Inc., USA) · FDA recall D-0316-2025
Class II · Mar 13, 2025 — CGMP Deviations (Glenmark Pharmaceuticals Inc., USA) · FDA recall D-0351-2025
Class II · Mar 13, 2025 — CGMP Deviations (Glenmark Pharmaceuticals Inc., USA) · FDA recall D-0352-2025
Class II · Mar 13, 2025 — CGMP Deviations (Glenmark Pharmaceuticals Inc., USA) · FDA recall D-0315-2025
Each entry is an official FDA enforcement report — look up any recall number in the FDA recall database ↗

🆔 Identity & classification

FDA NDC (as labeled) 16571-736-50
Product NDC 16571-736
11-digit billing NDC 16571073650
RxCUI 861156, 861164, 861171
UNII 33XCH0HOCD
Application # ANDA205956
SPL Set ID 36cf4555-6fe9-42d8-8d3b-3ca9c134a5b8
Established class (EPC) Antiarrhythmic
DEA schedule Non-controlled
Marketing category ANDA
Marketing status On market
FDA listing status Listed (active directory)
Marketing start 2020-12-16
Route ORAL
Dosage form CAPSULE, EXTENDED RELEASE
Substance PROPAFENONE HYDROCHLORIDE
GPI-14 35300050006920
GPI class Propafenone HCl ER
GCN Seq No 053538
GCN 21056
HICL code 004833
Ingredient (HICL) Propafenone Hcl
HIC1 code A
Therapeutic class — broad (HIC1) Cardiovascular System
HIC2 code A2
Therapeutic class — intermediate (HIC2) Cardiac Depressants
HIC3 code A2A
Therapeutic class — specific (HIC3) Antiarrhythmics
AHFS code 24:04.04.12
AHFS class Class Ic Antiarrhythmics
FDB label name PROPAFENONE HCL ER 225 MG CAP
FDB brand name Propafenone Hcl Er
Legend status F — Federal legend — prescription drug or device
TE code (Orange Book) AB · RLD · RS
Why two NDCs? The FDA registers this code as 16571-736-50 — a 5-3-2 layout, and that's what's printed on the package and shown on DailyMed. For insurance claims, every NDC is standardized to a uniform 11-digit 5-4-2 format by adding a zero to the product segment → 16571-0736-50. Same drug, same package — only the format differs.
Where does this data come from?
Identifiers from the FDA openFDA NDC Directory and Structured Product Labeling; RxCUI from RxNorm (NLM); GPI from Medi-Span; GCN / HIC / AHFS / legend from First Databank.

🏷️ RxNorm drug class

This medicine belongs to the Antiarrhythmic class.

Pharmacologic class Antiarrhythmic
Drug family (ATC) Antiarrhythmics, class Ic
Where does this data come from?
Therapeutic classes from RxNorm RxClass (U.S. National Library of Medicine) — Established Pharmacologic Class (FDA), ATC drug family (WHO) and mechanism of action, matched by this product’s RxCUI.

🏭 Manufacturer & labeler

LabelerRising Pharma Holdings, Inc.
Application holderRISING PHARMA HOLDINGS INC
FDA applicationANDA205956 (ANDA)
Labeler code16571
First marketedDec 2020
Product typeHuman Prescription Drug
Portfolio525 products on file
The labeler markets the product; the application holder owns the FDA approval. They’re often the same company but can differ (e.g. a repackager or an authorized generic). A mailing address / phone appears here when the manufacturer includes it in the product’s FDA label (not all do).
Where does this data come from?
Labeler, application holder and registered establishment from the FDA openFDA NDC Directory and Drugs@FDA; address/contact from the product’s FDA label.

🩺 Clinical

Label name PROPAFENONE HCL ER 225 MG CAP Ingredient Propafenone Hcl
📗 Our plain-language guide HelloPharmacist
  • Think of it as an electrical 'slow-down' for your heart. Your heart has channels that carry electrical signals triggering each beat — propafenone partially blocks those channels so...
  • What exactly is propafenone doing for my heart?
  • Yes, a few important ones. Grapefruit juice can raise propafenone levels in your blood, so it's best to avoid it. Several medications — including some antidepressants like paroxeti...
  • Are there foods or common medications I should avoid while taking this?
📖 Read our full Propafenone guide →

Supplement & herbal interactions

🌿 Drug–supplement interaction checker →
Where does this data come from?
Plain-language summary from MedlinePlus (U.S. National Library of Medicine); supplement & herbal interactions and nutrient depletion data from the Natural Medicines database; our full guide is HelloPharmacist editorial content.

🧪 Inactive Ingredients / Excipients

Inactive ingredients, also called excipients, are components of the drug product other than the active ingredient. They may include fillers, dyes, coatings, preservatives, flavors, or other formulation ingredients.

💡 Tap an ingredient (hover on desktop) to see what it is and why it’s used.

  • UNII 5138Q19F1X
    Ammonia is a colorless gas made from nitrogen and hydrogen. It's used in medicines as a pH buffer to maintain the correct acidity level and help keep the product stable.
  • UNII 35SW5USQ3G
    A synthetic yellow dye used to color medicines. It helps make tablets, capsules, and liquids visually distinct so patients can easily identify their medication.
  • UNII PN2ZH5LOQY
    A synthetic red dye approved by the FDA for use in foods, medicines, and cosmetics. It serves as a colorant to make tablets, capsules, and liquids visually distinctive for product identification.
  • UNII XM0M87F357
    A dark iron oxide compound that gives medicines their black or dark color. It's used as a colorant in tablets and capsules to help identify the product and make it visually distinctive.
  • UNII 2G86QN327L
    Gelatin is a protein derived from animal collagen, commonly used in medicines as a gelling agent and capsule material. It helps create soft or hard capsule shells that hold and release medication, and can also thicken liquid formulations.
  • UNII 3NXW29V3WO
    Hypromellose is a plant-based thickener made from cellulose. It's used in medicines as a binder to hold ingredients together, a coating for tablets, and a thickener for liquids.
  • UNII 70097M6I30
    Magnesium stearate is a salt made from magnesium and stearic acid, a fatty substance. It's used in tablets and capsules as a lubricant and glidant to help ingredients flow smoothly during manufacturing and prevent sticking.
  • UNII WZH3C48M4T
    Potassium hydroxide is a strong alkaline chemical used in medicines to adjust and maintain the pH level of liquid formulations, helping keep the product stable and the active ingredients effective.
  • UNII 6DC9Q167V3
    Propylene glycol is a clear liquid derived from petroleum or vegetable sources. It acts as a solvent, humectant, and preservative in medicines, helping dissolve active ingredients and maintain product stability.
  • UNII 46N107B71O
    Shellac is a natural resin secreted by the lac beetle. It's used as a coating on tablets and capsules to control how quickly the medicine dissolves and to improve appearance and stability.
  • UNII 15FIX9V2JP
    Titanium dioxide is a bright white mineral powder commonly used as a colorant and opacifying agent. It makes pills and tablets white or lighter in color and helps make coatings non-transparent.

11 inactive ingredients listed in the exact product block matched to this NDC.

Where does this data come from?
Data sourced from official FDA Structured Product Labeling (SPL) via DailyMed — ingredient classCode="IACT" elements from the exact product block matched by this NDC. Label-section narrative from DailyMed / the openFDA label index is shown separately when available.

Inactive ingredient FAQ

Are inactive ingredients the same for every manufacturer?
No. Inactive ingredients can differ by manufacturer, dosage form, strength, and package / product version.
Why might an inactive ingredient be missing?
Some SPLs do not provide a complete structured inactive-ingredient list, and older or unusual labels may only include the information in narrative text.
Can inactive ingredients matter?
Yes. They can matter for allergies, intolerances, dyes, gluten / lactose concerns, preservatives, and formulation differences — but confirm with a pharmacist or the manufacturer when it’s clinically important.

💲 Pricing

A drug doesn't have one price. Each row is a different public payment system, and none is what you'd pay at the counter — that depends on your insurance. The ⓘ on each row explains what it measures.

Price systemPer eachPer package
Retail pharmacies payNADAC · weekly Not in the retail survey — common for institutional, discontinued, or low-volume packs.
Medicaid paysCMS SDUD · 12 mo No recent Medicaid claims on file for this NDC — rare and low-volume NDCs are suppressed in the public data.
Medicare drug plans payPart D · Q2 2026 $0.9500 $475.00 / 500 capsules
Where does this data come from?
NADAC (National Average Drug Acquisition Cost) is the CMS weekly pharmacy-acquisition-cost survey — what pharmacies pay. ASP (Average Sales Price) is the CMS Medicare Part B drug-payment file, published quarterly. Medicaid pays is computed by us from CMS State Drug Utilization Data (total reimbursed ÷ units, trailing 12 months) — gross of rebates and inclusive of dispensing fees, so it reflects what Medicaid paid, not an acquisition cost. Medicare drug plans pay is the median negotiated point-of-sale unit cost across plans listing this NDC in the CMS quarterly Prescription Drug Plan pricing files, before rebates. The VA pays is the federal contract price (FSS, and the statutory Big 4 ceiling where listed) from the VA National Acquisition Center pharmaceutical price file. All are free public government data; each measures a different payer, so the figures are not directly comparable.

🔁 Therapeutic equivalents

ProductLabelerPackNADAC/unitTEStatusPrice vs. this
Propafenone Hydrochloride 225 mg 00832-0740-60 Upsher-Smith 60 capsules $0.356 AB Availability likely —
propafenone hydrochloride 225 mg 16714-0825-01 Northstar 60 capsules $0.356 AB Availability likely —
Propafenone Hydrochloride 225 mg 64380-0184-01 Strides 60 capsules $0.356 AB Discontinued —
propafenone hydrochloride 225 mg 68462-0408-60 Glenmark 60 capsules $0.356 AB Availability likely —
Propafenone Hydrochloride 225 mg 69680-0130-60 Vitruvias 60 capsules $0.356 AB Availability likely —
Propafenone Hydrochloride 225 mgthis 16571-0736-50 Rising 500 capsules — AB FDA listed —
Propafenone Hydrochloride 225 mg 59651-0276-05 Aurobindo 500 capsules — AB FDA listed —
Propafenone Hydrochloride 225 mg 68382-0522-05 Zydus 500 capsules — AB FDA listed —
Propafenone Hydrochloride 225 mg 70771-1525-05 Zydus 500 capsules — AB FDA listed —
About this product: this is a generic version of the medicine. FDA equivalence ratings are shown when available, and other versions are listed above, least expensive first.
Where does this data come from?
Equivalents are other NDCs of the same ingredient, form and route from the openFDA NDC Directory, ranked least-expensive-first by NADAC. Therapeutic-equivalence (AB) ratings come from the FDA Orange Book; biologics use the FDA Purple Book for biosimilar & interchangeable status.

⏳ Availability & generic status

🏛️
2020
On the market since
Dec 2020
📍
2026
Currently FDA-listed
6 years listed
🔓
·
Generic on the market
this product is a generic
✅This is a generic drug

This product is an FDA-approved generic. Other versions of the same drug are listed under Therapeutic equivalents, least expensive first.

Where does this data come from?
Patents and exclusivity from the FDA Orange Book (small-molecule drugs), refreshed from public FDA data. Generic launch timing is an estimate, not a guarantee.

💊 Medicaid utilization by pack size

Medicaid (SDUD) totals over the four most recent reported quarters for every package size of this drug — handy when a specific package (e.g. a starter/titration pack) carries little or no Medicaid volume on its own.
60 capsules16571-0736-06 77 Rx · $8,534
500 capsules this page16571-0736-50 No Medicaid data
Drug total (last 4 qtrs): 77 Rx · 9,954 units · $8,534 gross reimbursed
Tap a pack size to open its page. Source: CMS State Drug Utilization Data, last 4 quarters.

📦 Packaging — all sizes for this product

Package NDCDescription Per unit Per pack Marketing startStatus
16571-0736-06 60 CAPSULE, EXTENDED RELEASE in 1 BOTTLE (16571-736-06) $0.3557 / ea $21.34 2020-12-16 Active
16571-0736-50 You're viewing this 500 CAPSULE, EXTENDED RELEASE in 1 BOTTLE (16571-736-50) — — 2020-12-16 Active

You're viewing the largest of 2 pack sizes for this product.

Pack size FAQ

What quantity is in NDC 16571-0736-50?
NDC 16571-0736-50 is a 500-count package — 500 capsule, extended release in 1 bottle.
What is the difference between NDC 16571-0736-50 and NDC 16571-0736-06?
Both are PROPAFENONE HYDROCHLORIDE 225 mg Capsule, Extended Release — the drug itself is identical. NDC 16571-0736-50 is the 500-count package, while NDC 16571-0736-06 is the 60 capsules package.
What NDC number is used to bill for this package of PROPAFENONE HYDROCHLORIDE 225 mg Capsule, Extended Release?
Bill NDC 16571-0736-50 — the 11-digit billing format is 16571073650. Pharmacy and medical claims use the 11-digit form; the FDA label may print a shorter form of the same code.

Prices are the latest CMS NADAC pharmacy acquisition cost per NDC; per-pack figures are per-unit × pack quantity, shown only when the pack is denominated in the same measure NADAC prices.

🧭 About this NDC listing & data coverage

Finished prescription product
What data is (and isn’t) available for this NDC — tap to expand
NDC identity (package / product / labeler codes) ✓ Available
Labeler ✓ Available
Product & package description ✓ Available
Marketing category & status ✓ Available
Active ingredient / dosage form / route ✓ Available
FDA label (SPL via DailyMed) ✓ Available
Package photos ✓ Available
Inactive ingredients (structured) ✓ Available
NADAC pharmacy acquisition price (CMS) — Not published for this NDC CMS publishes NADAC only for NDCs reported in its retail-pharmacy survey.
Orange Book / therapeutic-equivalence data ✓ Available
HCPCS J-code billing crosswalk — Not published for this NDC Most self-administered / retail products have no J-code — that is normal.
Medicaid utilization (CMS SDUD) — Not published for this NDC CMS reports utilization only for NDCs with Medicaid claims above its privacy threshold.
“Not published” reflects what the public FDA / CMS / NLM sources provide for this exact package code — it is a property of the data feeds, not a judgment about the product.

Questions about this listing

Why is there no price listed?
The pricing shown on our NDC pages comes from CMS NADAC, a voluntary survey of retail community pharmacy invoices. CMS does not publish a NADAC for every NDC — packages outside the retail survey (institutional and hospital products, bulk packages, discontinued items, and many OTC items) may never receive one. A missing price reflects the survey's scope, not this product's actual cost, and does not mean the product is free or unavailable.
Is the NDC printed on the package the same as the 11-digit billing NDC?
Yes, they identify this exact package in different formats. The FDA registers it as 16571-736-50, which is what is printed on the packaging and shown on DailyMed. Insurance claims use a fixed 11-digit 5-4-2 format, so the short segment is padded with a leading zero: 16571-0736-50, written without dashes as 16571073650. The Identity section at the top of this page lists every form of this code.
What do the three segments of this NDC mean?
In 16571-0736-50, the first segment (16571) is the labeler code FDA assigned to Rising Pharma Holdings, Inc.; the middle segment (0736) identifies this specific product — its ingredient, strength, and dosage form; and the last segment (50) identifies this exact package size and type. Together they name one specific package of one specific product.
Is this package still being marketed?
Yes, per the latest FDA NDC Directory data on this page: this package is listed as actively marketed, with no marketing end date reported by Rising Pharma Holdings, Inc.. Listing status can change — the directory data on this page refreshes weekly.
Does this product come in other package sizes?
Yes — the FDA directory lists 1 other package presentation of this same product, including 60 capsules (16571-0736-06). Each has its own NDC and its own page — see the package list near the top of this page.
Who lists this product with the FDA?
Rising Pharma Holdings, Inc. is the labeler of record for this NDC — the company under whose FDA-assigned code the package is listed. The labeler may be the manufacturer itself or a distributor marketing the product under its own code.
Do I need a prescription for this product?
This NDC is listed with FDA as a prescription product, so it is dispensed under a prescriber's order. Your pharmacist can tell you whether any over-the-counter forms of the same medication exist.
This page identifies an FDA-listed package (the NDC) and reports public regulatory and pricing data about the listing. It is reference information, not a medical recommendation — talk to your pharmacist or prescriber about your own medication.
Where does this data come from?
Listing facts (marketing category, packager status, marketing dates) from the FDA openFDA NDC Directory; label availability from DailyMed; pricing coverage from CMS NADAC; equivalence scope from the FDA Orange Book.

📄 Full prescribing information FDA SPL

The complete FDA label for this product — the official prescribing information, verbatim, section by section. Jump with a chip, search within the label, or expand everything.
🚨 Boxed Warning 🎯 Indications and Usage ⏱️ Dosage and Administration 💊 Dosage Forms and Strengths ⛔ Contraindications ⚠️ Warnings and Cautions 🤒 Adverse Reactions 🔄 Drug Interactions 👥 Use in Specific Populations 🤰 Pregnancy 🧒 Pediatric Use 🧓 Geriatric Use 🆘 Overdosage 🧬 Clinical Pharmacology 🧬 Mechanism of Action 📦 How Supplied / Storage and Handling 📦 Storage and Handling 📋 Description 💬 Information for Patients
🚨 Boxed Warning ~1 min read ▾

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 patients 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 patients treated with encainide or flecainide (Class IC antiarrhythmics) compared with that seen in patients 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 patients treated with encainide or flecainide (Class IC antiarrhythmics) compared with that seen in patients 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.

🎯 Indications and Usage ~1 min read ▾

1 INDICATIONS AND USAGE Propafenone hydrochloride extended-release capsules are indicated to prolong the time to recurrence of symptomatic atrial fibrillation (AF) in patients with episodic (most likely paroxysmal or persistent) AF who do not have structural heart disease. Propafenone hydrochloride extended-release capsules are an antiarrhythmic indicated to prolong the time to recurrence of symptomatic atrial fibrillation (AF) in patients with episodic (most likely paroxysmal or persistent) AF who do not have structural heart disease.

( 1 ) Usage Considerations: Use in patients with permanent atrial fibrillation or with atrial flutter or paroxysmal supraventricular tachycardia (PSVT) has not been evaluated. Do not use to control ventricular rate during atrial fibrillation. ( 1 ) In patients with atrial fibrillation and atrial flutter, use propafenone hydrochloride extended-release capsules with drugs that increase the atrioventricular nodal refractory period.

( 1 ) The effect of propafenone on mortality has not been determined. ( 1 ) Usage Considerations: The use of propafenone hydrochloride extended-release capsules in patients with permanent AF or in patients exclusively with atrial flutter or paroxysmal supraventricular tachycardia (PSVT) has not been evaluated. Do not use propafenone hydrochloride extended-release capsules to control ventricular rate during AF.

Some patients with atrial flutter treated with propafenone have developed 1:1 conduction, producing an increase in ventricular rate. Concomitant treatment with drugs that increase the functional atrioventricular (AV) nodal refractory period is recommended. The effect of propafenone on mortality has not been determined [see Boxed Warning ] .

⏱️ Dosage and Administration ~1 min read ▾

2 DOSAGE AND ADMINISTRATION Propafenone hydrochloride extended-release capsules can be taken with or without food. Do not crush or further divide the contents of the capsule. The dose of propafenone hydrochloride extended-release capsules must be individually titrated on the basis of response and tolerance.

Initiate therapy with propafenone hydrochloride extended-release capsules 225 mg given every 12 hours. Dosage may be increased at a minimum of 5-day intervals to 325 mg given every 12 hours. If additional therapeutic effect is needed, the dose of propafenone hydrochloride extended-release capsules may be increased to 425 mg given every 12 hours.

In patients with hepatic impairment or those with significant widening of the QRS complex or second- or third-degree AV block, consider reducing the dose. The combination of cytochrome P450 3A4 (CYP3A4) inhibition and either cytochrome P450 2D6 (CYP2D6) deficiency or CYP2D6 inhibition with the simultaneous administration of propafenone may significantly increase the concentration of propafenone and thereby increase the risk of proarrhythmia and other adverse events. Therefore, avoid simultaneous use of propafenone hydrochloride extended-release capsules with both a CYP2D6 inhibitor and a CYP3A4 inhibitor [see Warnings and Precautions (5.4) , Drug Interactions (7.1) ] .

Initiate therapy with 225 mg given every 12 hours. ( 2 ) Dosage may be increased at a minimum of 5-day intervals to 325 mg every 12 hours and, if necessary, to 425 mg every 12 hours. ( 2 ) Consider reducing the dose in patients with hepatic impairment, significant widening of the QRS complex, or second- or third-degree AV block.

( 2 )

💊 Dosage Forms and Strengths 154 words ▾

3 DOSAGE FORMS AND STRENGTHS Propafenone hydrochloride extended-release capsules are supplied as hard-shell gelatin capsules filled with white to off white round, biconvex mini tablets containing 225 mg, 325 mg, or 425 mg of propafenone hydrochloride. The 225 mg capsule is an orange opaque cap and a white opaque body, with 'I 146' imprinted on cap in black ink, containing white to off white, round, biconvex mini tablets plain on both sides. The 325 mg capsule is a blue opaque cap and a white opaque body, with 'I 145' imprinted on cap in black ink, containing white to off white, round, biconvex mini tablets plain on both sides.

The 425 mg capsule is a green opaque cap and a white opaque body, with 'I 144' imprinted on cap in black ink, containing white to off white, round, biconvex mini tablets plain on both sides. Capsules: 225 mg, 325 mg, 425 mg. ( 3 )

⛔ Contraindications 115 words ▾

4 CONTRAINDICATIONS Propafenone hydrochloride extended-release capsules are contraindicated in the following circumstances: Heart failure Cardiogenic shock Sinoatrial, atrioventricular, and intraventricular disorders of impulse generation or conduction (e.g., sick sinus node syndrome, AV block) in the absence of an artificial pacemaker Known Brugada Syndrome Bradycardia Marked hypotension Bronchospastic disorders or severe obstructive pulmonary disease Marked electrolyte imbalance Heart failure ( 4 ) Cardiogenic shock ( 4 ) Sinoatrial, atrioventricular, and intraventricular disorders of impulse generation and/or conduction in the absence of pacemaker ( 4 ) Known Brugada Syndrome ( 4 ) Bradycardia ( 4 ) Marked hypotension ( 4 ) Bronchospastic disorders and severe obstructive pulmonary disease ( 4 ) Marked electrolyte imbalance ( 4 )

⚠️ Warnings and Cautions ~3 min read ▾

5 WARNINGS AND PRECAUTIONS May cause new or worsened arrhythmias. Evaluate patients via ECG prior to and during therapy. ( 5.1 ) Propafenone hydrochloride extended-release capsules may unmask Brugada or Brugada-like Syndrome.

Evaluate patients via ECG after initiation of therapy. ( 4 , 5.2 ) Avoid use with other antiarrhythmic agents or drugs that prolong the QT interval. ( 5.3 ) Avoid simultaneous use of propafenone with both a cytochrome P450 2D6 (CYP2D6) inhibitor and a 3A4 inhibitor (CYP3A4).

( 5.4 ) May provoke overt heart failure. ( 5.5 ) May cause dose-related first-degree AV block or other conduction disturbances. Should not be given to patients with conduction defects in absence of a pacemaker.

( 5.6 ) May affect artificial pacemakers. Pacemakers should be monitored during therapy. ( 5.7 ) Agranulocytosis: Patients should report signs of infection.

( 5.8 ) Administer cautiously to patients with impaired hepatic and renal function. ( 5.9 , 5.10 ) Exacerbation of myasthenia gravis has been reported. ( 5.11 )

5.1Proarrhythmic 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 extended-release capsules be evaluated electrocardiographically prior to and during therapy to determine whether the response to propafenone hydrochloride extended-release capsules 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 the Propafenone Hydrochloride Extended-Release Capsules Atrial Fibrillation Trial (RAFT) trial [see Clinical Studies (14) ] , there were too few deaths to assess the long-term risk to patients.

There were 5 deaths, 3 in the pooled group for propafenone hydrochloride extended-release capsules (0.8%), and 2 in the placebo group (1.6%). In the overall database of 8 trials of propafenone hydrochloride extended-release capsules 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.

In a U.S. uncontrolled, open-label, multicenter trial using the immediate-release formulation in patients with symptomatic supraventricular tachycardia (SVT), 1.9% (9/474) of these patients experienced ventricular tachycardia (VT) or ventricular fibrillation (VF) during the trial. However, in 4 of the 9 patients, the ventricular tachycardia was of atrial origin. Six of the 9 patients that developed ventricular arrhythmias did so within 14 days of onset of therapy.

About 2.3% (11/474) of all patients had recurrence of SVT during the trial which could have been a change in the patients' 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, torsades de pointes, asystole, and death. Overall in clinical trials with propafenone hydrochloride immediate-release (which included patients treated for ventricular arrhythmias, atrial fibrillation/flutter, and PSVT), 4.7% of all patients 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 patients 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 patients with less serious or benign arrhythmias, which include pat…

🤒 Adverse Reactions ~3 min read ▾

6 ADVERSE REACTIONS The most commonly reported adverse events with propafenone (greater than 5% and greater than placebo) excluding those not reasonably associated with the use of the drug included the following: dizziness, palpitations, chest pain, dyspnea, taste disturbance, nausea, fatigue, anxiety, constipation, upper respiratory tract infection, edema, and influenza. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Rising Pharma Holdings, Inc. at 1-844-874-7464 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.

6.1Clinical 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. The data described below reflect exposure to propafenone hydrochloride extended-release capsules 225 mg twice daily in 126 patients, to propafenone hydrochloride extended-release capsules 325 mg twice daily in 135 patients, to propafenone hydrochloride extended-release capsules 425 mg twice daily in 136 patients, and to placebo in 126 patients for up to 39 weeks (mean: 20 weeks) in a placebo- controlled trial (RAFT) conducted in the U.S.

The most commonly reported adverse events with propafenone (greater than 5% and greater than placebo) excluding those not reasonably associated with the use of the drug or because they were associated with the condition being treated, were dizziness, palpitations, chest pain, dyspnea, taste disturbance, nausea, fatigue, anxiety, constipation, upper respiratory tract infection, edema, and influenza. The frequency of discontinuation due to adverse events was 17%, and the rate was highest during the first 14 days of treatment.

Cardiac-related adverse events occurring in greater than or equal to 2% of the patients in any of the RAFT propafenone extended-release capsules treatment groups and more common with propafenone than with placebo, excluding those that are common in the population and those not plausibly related to drug therapy, included the following: angina pectoris, atrial flutter, AV block first-degree, bradycardia, congestive cardiac failure, cardiac murmur, edema, dyspnea, rales, wheezing, and cardioactive drug level above therapeutic.

Propafenone prolongs the PR and QRS intervals in patients with atrial and ventricular arrhythmias. Prolongation of the QRS interval makes it difficult to interpret the effect of propafenone on the QT interval [see Clinical Pharmacology (12.2) ]. Non-cardiac related adverse events occurring in greater than or equal to 2% of the patients in any of the RAFT propafenone extended-release capsules treatment groups and more common with propafenone than with placebo, excluding those that are common in the population and those not plausibly related to drug therapy, included the following: blurred vision, constipation, diarrhea, dry mouth, flatulence, nausea, vomiting, fatigue, weakness, upper respiratory tract infection, blood alkaline phosphatase increased, hematuria, muscle weakness, dizziness (excluding vertigo), headache, taste disturbance, tremor, somnolence, anxiety, depression, ecchymosis.

No clinically important differences in incidence of adverse reactions were noted by age or gender. Too few non-Caucasian patients were enrolled to assess adverse events according to race. Adverse events occurring in 2% or more of the patients in any of the ERAFT [see Clinical Studies (14) ] propafenone hydrochloride extended-release capsules treatment groups and not listed above include the following: bundle branch block left, bundle branch block right, conduction disorders, sinus bradycardia, and hypotension.

Other adverse events reported with propafenone clinical trials not already listed elsewhere in the prescribing information include the following adverse events by body system and preferred term. Blood and Lymphatic System Anemia, lymphadenopathy, spleen dis…

🔄 Drug Interactions ~3 min read ▾

7 DRUG INTERACTIONS Inhibitors of CYP2D6, 1A2, and 3A4 may increase propafenone levels which may lead to cardiac arrhythmias. Simultaneous use with both a CYP3A4 and CYP2D6 inhibitor (or in patients with CYP2D6 deficiency) should be avoided. ( 7.1 ) Propafenone may increase digoxin or warfarin levels.

( 7.2 , 7.3 ) Orlistat may reduce propafenone concentrations. Abrupt cessation of orlistat in patients stable on propafenone hydrochloride extended-release capsules has resulted in convulsions, atrioventricular block, and circulatory failure. ( 7.4 ) Concomitant use of lidocaine may increase central nervous system side effects.

( 7.6 )

7.1CYP2D6 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. The combination of CYP3A4 inhibition and either CYP2D6 deficiency or CYP2D6 inhibition with administration of propafenone may increase the risk of adverse reactions, including proarrhythmia. Therefore, simultaneous use of propafenone hydrochloride extended-release capsules with both a CYP2D6 inhibitor and a CYP3A4 inhibitor should be avoided [see Warnings and Precautions (5.4) , Dosage and Administration (2) ].

Amiodarone Concomitant administration of propafenone and amiodarone can affect conduction and repolarization and is not recommended. Cimetidine Concomitant administration of propafenone immediate-release tablets and cimetidine in 12 healthy subjects resulted in a 20% increase in steady-state plasma concentrations of propafenone. Fluoxetine Concomitant administration of propafenone and fluoxetine in extensive metabolizers increased the S-propafenone C max and AUC by 39% and 50%, respectively, and the R-propafenone C max and AUC by 71% and 50%, respectively.

Quinidine Small doses of quinidine completely inhibit the CYP2D6 hydroxylation metabolic pathway, making all patients, in effect, slow metabolizers [see Clinical Pharmacology (12.3) ] . Concomitant administration of quinidine (50 mg 3 times daily) with 150-mg immediate-release propafenone 3 times daily decreased the clearance of propafenone by 60% in extensive metabolizers, making them poor metabolizers. Steady-state plasma concentrations increased by more than 2-fold for propafenone and decreased 50% for 5-OH-propafenone.

A 100-mg dose of quinidine increased steady-state concentrations of propafenone 3-fold. Avoid concomitant use of propafenone and quinidine. Rifampin Concomitant administration of rifampin and propafenone in extensive metabolizers decreased the plasma concentrations of propafenone by 67% with a corresponding decrease of 5-OH- propafenone by 65%.

The concentrations of norpropafenone increased by 30%. In poor metabolizers, there was a 50% decrease in propafenone plasma concentrations and an increase in the AUC and C max of norpropafenone by 74% and 20%, respectively. Urinary excretion of propafenone and its metabolites decreased significantly.

Similar results were noted in elderly patients: Both the AUC and C max of propafenone decreased by 84%, with a corresponding decrease in AUC and C max of 5-OH-propafenone by 69% and 57%, respectively.

7.2Digoxin Concomitant use of propafenone and digoxin increased steady-state serum digoxin exposure (AUC) in patients by 60% to 270% and decreased the clearance of digoxin by 31% to 67%. Monitor plasma digoxin levels of patients receiving propafenone and adjust digoxin dosage as needed.

7.3Warfarin The concomitant administration of propafenone and warfarin increased warfarin plasma concentrations at steady state by 39% in healthy volunteers and prolonged the prothrombin time (PT) in patients taking warfarin. Adjust the warfarin dose as needed by monitoring INR (international normalized ratio).

7.4Orlistat Orlistat may limit the fraction of propafenone available for absorption. In postmarketing reports, abrupt cessation…

👥 Use in Specific Populations ~3 min read ▾

8 USE IN SPECIFIC POPULATIONS

8.1Pregnancy Risk Summary In the absence of studies in pregnant women, available data from published case reports and several decades of postmarketing experience with use of propafenone hydrochloride in pregnancy have not identified any drug-associated risks of miscarriage, birth defects, or adverse maternal or fetal outcomes. Untreated arrhythmias during pregnancy may pose a risk to the pregnant woman and fetus (see Clinical Considerations ). Propafenone and its metabolite, 5-OH-propafenone, cross the placenta in humans.

In animal studies, propafenone was not teratogenic. At maternally toxic doses (ranging from 2 to 6 times the maximum recommended human dose [MRHD]), there was evidence of adverse developmental outcomes when administered to pregnant rabbits and rats during organogenesis or when administered to pregnant rats during mid-gestation through weaning of their offspring (see Data ) . The estimated background risks of major birth defects and miscarriage for the indicated populations are unknown.

All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2% to 4% and 15% to 20%, respectively. Clinical Considerations Disease-associated maternal and/or embryo/fetal risk: The incidence of VT is increased and may be more symptomatic during pregnancy.

Ventricular arrhythmias most often occur in pregnant women with underlying cardiomyopathy, congenital heart disease, valvular heart disease, or mitral valve prolapse. Breakthrough arrhythmias may also occur during pregnancy, as therapeutic treatment levels may be difficult to maintain due to the increased volume of distribution and increased drug metabolism inherent in the pregnant state. Fetal/Neonatal Adverse Reactions: Propafenone and its metabolite have been shown to cross the placenta.

Adverse reactions such as fetal/neonatal arrhythmias have been associated with the use of other antiarrhythmic agents by pregnant women. Fetal/neonatal monitoring for signs and symptoms of arrhythmia is recommended during and after treatment of pregnant women with propafenone. Labor or Delivery: Risk of arrhythmias may increase during labor and delivery.

Patients treated with propafenone hydrochloride should be monitored continuously for arrhythmias during labor and delivery [see Warnings and Precautions (5.1) ] . Data Propafenone has been shown to cause embryo-fetal mortality in rabbits and rats when given orally during organogenesis at maternally toxic doses of 150 mg/kg/day (rabbit: maternal mortality, decreased body weight gain and food consumption at approximately 3 times the MRHD on a mg/m 2 basis) and 600 mg/kg/day (rat: maternal decreased body weight gain and food consumption at approximately 6 times the MRHD on a mg/m 2 basis).

In addition, a maternally toxic dose of 600 mg/kg/day (approximately 6 times the MRHD on a mg/m 2 basis) also caused decreased fetal weights in rats. Increased placental weights and delayed ossification occurred in rabbits at a dose of 30 mg/kg/day (less than the MRHD on a mg/m 2 basis) in the absence of maternal toxicity. No adverse developmental outcomes in the absence of maternal toxicity were seen following oral doses of 15 mg/kg/day to rabbits or up to 270 mg/kg/day to rats administered during organogenesis (equivalent to 0.3 times or approximately 3 times the MRHD on a mg/m 2 basis, respectively).

In an oral study, female rats received propafenone up to 500 mg/kg/day from mid-gestation through weaning. At 90 mg/kg/day (equivalent to the MRHD on a mg/m 2 basis), there were no adverse developmental outcomes in the absence of maternal toxicity. However, doses ≥180 mg/kg/day (2 or more times the MRHD on a mg/m 2 basis) produced increases in maternal deaths and resulted in reductions in neonatal survival, body weight gain, and delayed development in the presen…

🤰 Pregnancy ~3 min read ▾

8.1Pregnancy Risk Summary In the absence of studies in pregnant women, available data from published case reports and several decades of postmarketing experience with use of propafenone hydrochloride in pregnancy have not identified any drug-associated risks of miscarriage, birth defects, or adverse maternal or fetal outcomes. Untreated arrhythmias during pregnancy may pose a risk to the pregnant woman and fetus (see Clinical Considerations ). Propafenone and its metabolite, 5-OH-propafenone, cross the placenta in humans.

In animal studies, propafenone was not teratogenic. At maternally toxic doses (ranging from 2 to 6 times the maximum recommended human dose [MRHD]), there was evidence of adverse developmental outcomes when administered to pregnant rabbits and rats during organogenesis or when administered to pregnant rats during mid-gestation through weaning of their offspring (see Data ) . The estimated background risks of major birth defects and miscarriage for the indicated populations are unknown.

All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2% to 4% and 15% to 20%, respectively. Clinical Considerations Disease-associated maternal and/or embryo/fetal risk: The incidence of VT is increased and may be more symptomatic during pregnancy.

Ventricular arrhythmias most often occur in pregnant women with underlying cardiomyopathy, congenital heart disease, valvular heart disease, or mitral valve prolapse. Breakthrough arrhythmias may also occur during pregnancy, as therapeutic treatment levels may be difficult to maintain due to the increased volume of distribution and increased drug metabolism inherent in the pregnant state. Fetal/Neonatal Adverse Reactions: Propafenone and its metabolite have been shown to cross the placenta.

Adverse reactions such as fetal/neonatal arrhythmias have been associated with the use of other antiarrhythmic agents by pregnant women. Fetal/neonatal monitoring for signs and symptoms of arrhythmia is recommended during and after treatment of pregnant women with propafenone. Labor or Delivery: Risk of arrhythmias may increase during labor and delivery.

Patients treated with propafenone hydrochloride should be monitored continuously for arrhythmias during labor and delivery [see Warnings and Precautions (5.1) ] . Data Propafenone has been shown to cause embryo-fetal mortality in rabbits and rats when given orally during organogenesis at maternally toxic doses of 150 mg/kg/day (rabbit: maternal mortality, decreased body weight gain and food consumption at approximately 3 times the MRHD on a mg/m 2 basis) and 600 mg/kg/day (rat: maternal decreased body weight gain and food consumption at approximately 6 times the MRHD on a mg/m 2 basis).

In addition, a maternally toxic dose of 600 mg/kg/day (approximately 6 times the MRHD on a mg/m 2 basis) also caused decreased fetal weights in rats. Increased placental weights and delayed ossification occurred in rabbits at a dose of 30 mg/kg/day (less than the MRHD on a mg/m 2 basis) in the absence of maternal toxicity. No adverse developmental outcomes in the absence of maternal toxicity were seen following oral doses of 15 mg/kg/day to rabbits or up to 270 mg/kg/day to rats administered during organogenesis (equivalent to 0.3 times or approximately 3 times the MRHD on a mg/m 2 basis, respectively).

In an oral study, female rats received propafenone up to 500 mg/kg/day from mid-gestation through weaning. At 90 mg/kg/day (equivalent to the MRHD on a mg/m 2 basis), there were no adverse developmental outcomes in the absence of maternal toxicity. However, doses ≥180 mg/kg/day (2 or more times the MRHD on a mg/m 2 basis) produced increases in maternal deaths and resulted in reductions in neonatal survival, body weight gain, and delayed development in the presence of maternal toxicity.

🧒 Pediatric Use 16 words ▾

8.4Pediatric Use The safety and effectiveness of propafenone in pediatric patients have not been established.

🧓 Geriatric Use 74 words ▾

8.5Geriatric Use Of the total number of subjects in Phase 3 clinical trials of propafenone hydrochloride extended-release capsules 46% were 65 and older, while 16% were 75 and older. No overall differences in safety or effectiveness were observed between these subjects and younger subjects, but greater sensitivity of some older individuals at higher doses cannot be ruled out. The effect of age on the pharmacokinetics and pharmacodynamics of propafenone has not been studied.

🆘 Overdosage 102 words ▾

10 OVERDOSAGE The symptoms of overdosage may include hypotension, somnolence, bradycardia, intra-atrial and intraventricular conduction disturbances, and rarely, convulsions and high-grade ventricular arrhythmias. Defibrillation, as well as infusion of dopamine and isoproterenol, has been effective in controlling abnormal rhythm and blood pressure. Convulsions have been alleviated with intravenous diazepam.

General supportive measures such as mechanical respiratory assistance and external cardiac massage may be necessary. The hemodialysis of propafenone in patients with an overdose is expected to be of limited value in the removal of propafenone as a result of both its high protein binding (greater than 95%) and large volume of distribution.

🧬 Clinical Pharmacology ~3 min read ▾

12 CLINICAL PHARMACOLOGY

12.1Mechanism of Action Propafenone is a Class 1C antiarrhythmic drug with local anesthetic effects and a direct stabilizing action on myocardial membranes. The electrophysiological effect of propafenone manifests itself in a reduction of upstroke velocity (Phase 0) of the monophasic action potential. In Purkinje fibers, and, to a lesser extent, myocardial fibers, propafenone reduces the fast inward current carried by sodium ions.

Diastolic excitability threshold is increased and effective refractory period prolonged. Propafenone reduces spontaneous automaticity and depresses triggered activity. Studies in anesthetized dogs and isolated organ preparations show that propafenone has beta- sympatholytic activity at about 1/50 the potency of propranolol.

Clinical studies employing isoproterenol challenge and exercise testing after single doses of propafenone indicate a beta- adrenergic blocking potency (per mg) about 1/40 that of propranolol in man. In clinical trials with the immediate-release formulation, resting heart rate decreases of about 8% were noted at the higher end of the therapeutic plasma concentration range. At very high concentrations in vitro, propafenone can inhibit the slow inward current carried by calcium, but this calcium antagonist effect probably does not contribute to antiarrhythmic efficacy.

Moreover, propafenone inhibits a variety of cardiac potassium currents in in vitro studies (i.e., the transient outward, the delayed rectifier, and the inward rectifier current). Propafenone has local anesthetic activity approximately equal to procaine. Compared with propafenone, the main metabolite, 5- hydroxypropafenone, has similar sodium and calcium channel activity, but about 10 times less beta-blocking activity.

(N-depropylpropafenone has weaker sodium channel activity but equivalent affinity for beta-receptors.)

12.2Pharmacodynamics Cardiac Electrophysiology Electrophysiology trials in patients with ventricular tachycardia have shown that propafenone prolongs atrioventricular conduction while having little or no effect on sinus node function. Both atrioventricular nodal conduction time (AH interval) and His-Purkinje conduction time (HV interval) are prolonged. Propafenone has little or no effect on the atrial functional refractory period, but AV nodal functional and effective refractory periods are prolonged.

In patients with Wolff-Parkinson-White syndrome, propafenone hydrochloride immediate-release tablets reduce conduction and increase the effective refractory period of the accessory pathway in both directions. Electrocardiograms: Propafenone prolongs the PR and QRS intervals. Prolongation of the QRS interval makes it difficult to interpret the effect of propafenone on the QT interval.

Table 1. Mean Change ± SD in 12-Lead Electrocardiogram Results (RAFT) Propafenone Hydrochloride Extended-Release Capsules Twice-Daily Dosing Placebo 225 mg 325 mg 425 mg n = 126 n = 135 n = 136 n = 126 PR (ms) 9 ± 22 12 ± 23 21 ± 24 1 ± 16 QRS (ms) 4 ± 14 6 ± 15 6 ± 15 -2 ± 12 Heart rate 5 ± 24 7 ± 23 2 ± 22 8 ± 27 QTc Calculated using Bazett's correction factor. (ms) 2 ± 30 5 ± 36 6 ± 37 5 ± 35 In RAFT [see Clinical Studies (14) ] , the distribution of the maximum changes in QTc compared with baseline over the trial in each patient was similar in the groups receiving propafenone hydrochloride extended-release capsules 225 mg twice daily, 325 mg twice daily, and 425 mg twice daily, and placebo.

Similar results were seen in the ERAFT trial. Table 2. Number of Patients According to the Range of Maximum QTc Change Compared with Baseline over the Trial in Each Dose Group (RAFT Trial).

Propafenone Hydrochloride Extended-Release Capsules Range Maximum QTc Change 225 mg Twice Daily N = 119 n (%) 325 mg Twice Daily N = 129 n (%) 425 mg Twice Daily N = 123 n (%) Placebo N = 100 n (%) >20% 1 (1) 6 (5) 3 (2) 5 (4) 10-20% 19 (16) 28 (22) 32 (26) 24 (20) 0 ≤10% 99 (83) 95 (74) 88 (72) 91 (76) Hemodynamics Trials i…

🧬 Mechanism of Action ~1 min read ▾

12.1Mechanism of Action Propafenone is a Class 1C antiarrhythmic drug with local anesthetic effects and a direct stabilizing action on myocardial membranes. The electrophysiological effect of propafenone manifests itself in a reduction of upstroke velocity (Phase 0) of the monophasic action potential. In Purkinje fibers, and, to a lesser extent, myocardial fibers, propafenone reduces the fast inward current carried by sodium ions.

Diastolic excitability threshold is increased and effective refractory period prolonged. Propafenone reduces spontaneous automaticity and depresses triggered activity. Studies in anesthetized dogs and isolated organ preparations show that propafenone has beta- sympatholytic activity at about 1/50 the potency of propranolol.

Clinical studies employing isoproterenol challenge and exercise testing after single doses of propafenone indicate a beta- adrenergic blocking potency (per mg) about 1/40 that of propranolol in man. In clinical trials with the immediate-release formulation, resting heart rate decreases of about 8% were noted at the higher end of the therapeutic plasma concentration range. At very high concentrations in vitro, propafenone can inhibit the slow inward current carried by calcium, but this calcium antagonist effect probably does not contribute to antiarrhythmic efficacy.

Moreover, propafenone inhibits a variety of cardiac potassium currents in in vitro studies (i.e., the transient outward, the delayed rectifier, and the inward rectifier current). Propafenone has local anesthetic activity approximately equal to procaine. Compared with propafenone, the main metabolite, 5- hydroxypropafenone, has similar sodium and calcium channel activity, but about 10 times less beta-blocking activity.

(N-depropylpropafenone has weaker sodium channel activity but equivalent affinity for beta-receptors.)

📦 How Supplied / Storage and Handling 219 words ▾

16 HOW SUPPLIED/STORAGE AND HANDLING Propafenone Hydrochloride Extended-Release Capsules, USP 225 mg are available as hard gelatin capsules containing 225 mg of propafenone HCl. The capsule is an orange opaque cap and a white opaque body, with 'I 146' imprinted on cap in black ink, containing white to off white, round, biconvex mini tablets plain on both sides. NDC 16571-736-06 Bottles of 60 capsules NDC 16571-736-50 Bottles of 500 capsules Propafenone Hydrochloride Extended-Release Capsules, USP 325 mg are available as hard gelatin capsules containing 325 mg of propafenone HCl.

The capsule is a blue opaque cap and a white opaque body, with 'I 145' imprinted on cap in black ink, containing white to off white, round, biconvex mini tablets plain on both sides. NDC 16571-737-06 Bottles of 60 capsules NDC 16571-737-50 Bottles of 500 capsules Propafenone Hydrochloride Extended-Release Capsules, USP 425 mg are available as hard gelatin capsules containing 425 mg of propafenone HCl. The capsule is a green opaque cap and a white opaque body, with 'I 144' imprinted on cap in black ink, containing white to off white, round, biconvex mini tablets plain on both sides.

NDC 16571-738-06 Bottles of 60 capsules NDC 16571-738-50 Bottles of 500 capsules Storage: Store at 25°C (77°F); excursions permitted to 15°C to 30°C (59°F to 86°F). Dispense in a tight container.

📦 Storage and Handling 19 words ▾

Storage: Store at 25°C (77°F); excursions permitted to 15°C to 30°C (59°F to 86°F). Dispense in a tight container.

📋 Description 186 words ▾

11 DESCRIPTION Propafenone Hydrochloride Extended-Release Capsules, USP are an antiarrhythmic drug supplied in extended- release capsules of 225, 325, and 425 mg for oral administration. Chemically, propafenone hydrochloride is 2'-[2-hydroxy-3-(propylamino)-propoxy]-3- phenylpropiophenone hydrochloride, with a molecular weight of 377.92. The molecular formula is C 21 H 27 NO 3 ∙HCl.

Propafenone HCl has some structural similarities to beta-blocking agents. The structural formula of propafenone HCl is given below: Propafenone HCl occurs as colorless crystals or white crystalline powder with a very bitter taste. It is slightly soluble in water (20°C), chloroform, and ethanol.

Propafenone Hydrochloride Extended-Release Capsules, USP are filled with white to off white round, biconvex mini tablets containing propafenone and the following inactive ingredients: hypromellose and magnesium stearate. Each capsule contains titanium dioxide and gelatin. In addition, the 225 mg capsule contains D&C Yellow No.

10 and FD&C Red No. 3, the 325 mg capsule contains FD&C Blue No. 2, and the 425 mg capsule contains FD&C Green No.

3. The black imprinting ink consists of black iron oxide (ferrosoferric oxide), propylene glycol, potassium hydroxide, shellac, and ammonium hydroxide. USP Dissolution Test Pending Chemical Structure

💬 Information for Patients 81 words ▾

17 PATIENT COUNSELING INFORMATION Advise the patient to read the FDA-approved patient labeling (Patient Information). Instruct patients to notify their healthcare providers of any change in over-the-counter, prescription, and supplement use. Instruct patients to report symptoms that may be associated with altered electrolyte balance, such as excessive or prolonged diarrhea, sweating, vomiting, or loss of appetite or thirst.

Instruct patients not to double the next dose if a dose is missed. The next dose should be taken at the usual time.

Source: FDA Structured Product Labeling, mirrored from DailyMed / openFDA. Prefer the government’s original formatting? View this label on DailyMed ↗
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For educational and professional reference only — not medical advice. Pricing reflects published NADAC and CMS ASP (free public data) and may differ from your acquisition cost; always verify before billing or dispensing.