What should I avoid while taking Flecainide 4mg/5ml oral solution?

Take with or without food. The absorption is unaffected by food. (Source: DrugBank, licensed under CC BY-NC 4.0)

Do I need a prescription for Flecainide 4mg/5ml oral solution?

Flecainide 4mg/5ml oral solution is classified as a Valid as a prescribable product in the UK. However, always consult a pharmacist or doctor before use. (Source: NHS dm+d)

What are the brand names for Flecainide 4mg/5ml oral solution?

Flecainide 4mg/5ml oral solution is the generic name. It is available under brand names including: Flecainide 4mg/5ml oral solution. (Source: NHS dm+d — Actual Medicinal Products)

Flecainide 4mg/5ml oral solution

Prescription only

Requires a prescription from a doctor or prescriber

Oral solution

4mg/5ml

Oral

Anti-arrhythmic drugs

Active ingredients:

Flecainide

BNF classificationBrowse formulary

Where this medicine sits in the British National Formulary — the UK's standard prescribing reference

BNF 02.03.02

ATC classificationBrowse ATC index

International classification by the WHO, grouping medicines by the organ system they act on

ATC C01BC04

Chemical classBrowse classes

Classification based on the molecule's chemical structure and properties

Check interactions for Flecainide

No active safety alerts

Official documents, adverse reaction reporting, and safety monitoring

Report a side effect

Submit a Yellow Card report to the MHRA

Official medicine documents

Yellow Card

Report side effects (MHRA)

Drug safety updates

MHRA alerts for Flecainide

Source: MHRA Products DatabaseOGL 3.0

Updated 3 months ago(16 Jan 2026)

Safety monitoring data

Yellow Card reports

MHRA

The MHRA Yellow Card scheme collects reports of suspected side effects from healthcare professionals and patients. View the Drug Analysis Profile (iDAP) for real-world adverse reaction data.

View Drug Analysis Profile

Suspected adverse reactions reported for Flecainide

Browse all iDAP reports

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Report a side effect

Submit a Yellow Card report to the MHRA

Data from the MHRA Yellow Card scheme. A reported reaction does not necessarily mean the medicine caused it. Contains public sector information licensed under the Open Government Licence v3.0.

EudraVigilance

EMA

The European Medicines Agency (EMA) collects suspected adverse reaction reports from across the EU/EEA through the EudraVigilance system. Search for safety data on this medicine.

View EudraVigilance report

Suspected adverse reactions reported for Flecainide

About EudraVigilance

Learn about EU pharmacovigilance and safety monitoring

EudraVigilance data is published by the European Medicines Agency (EMA). A suspected adverse reaction is not necessarily caused by the medicine.

1 branded products available

1 productsShow details

Part of the Tambocor brand family (generic: Flecainide)

1 products

Possibly available on the UK marketRestricted supplyDiscontinuedAvailability per NHS dm+d

MHRA licensed products

View all licensed products for Flecainide on the MHRA register

Flecainide 4mg/5ml oral solution

Special Order

None

Special

Source: NHS dm+dOGL 3.0

Updated about 1 month ago(1 Mar 2026)

Daily doseShow details

WHO defined daily dose (DDD)

200 mg

Not a recommended dose. The DDD is the assumed average maintenance dose per day for a drug used for its main indication in adults. It is a statistical measure used for research and comparison purposes only.

Source: WHO Collaborating Centre for Drug Statistics Methodology, distributed via NHS dm+d BNF mapping files. Contains public sector information licensed under the Open Government Licence v3.0.

Therapeutically similar medicines

10 similarShow details

Flecainide 25mg/5ml oral solution sugar free

Oral solution

25mg/5ml

Same therapeutic group

Propafenone 150mg/5ml oral suspension

Oral suspension

150mg/5ml

Same therapeutic group

Propafenone 150mg/5ml oral solution

Oral solution

150mg/5ml

Same therapeutic group

Propafenone 50mg/5ml oral suspension

Oral suspension

50mg/5ml

Same therapeutic group

Propafenone 50mg/5ml oral solution

Oral solution

50mg/5ml

Same therapeutic group

Similarity based on WHO Anatomical Therapeutic Chemical (ATC) classification and NHS BNF section grouping. Source data: NHS dm+d via TRUD (OGL v3.0), WHO ATC/DDD Index.

NHS prescribing volume and spending trends

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Loading prescribing data...

Clinical guidelines and formulary information

British National Formulary

Flecainide

BNF

Drug monograph — bnf.nice.org.uk

Source: British National Formulary, NICE. Joint Formulary Committee. Contains public sector information licensed under the Open Government Licence v3.0.

NICE clinical guidance(3)

Atrial fibrillation: diagnosis and management (NG196)

NG196

NICE guideline

Updated Jun 2021

Depression in adults with a chronic physical health problem: recognition and management (CG91)

CG91

Clinical guideline

Updated Oct 2009

Mexiletine for treating the symptoms of myotonia in non-dystrophic myotonic disorders (TA748)

TA748

Technology appraisal

Updated Dec 2021

Source: National Institute for Health and Care Excellence (NICE). Contains public sector information licensed under the Open Government Licence v3.0.

Check stock at pharmacies and supply information

Show details

Pharmacy stock checkers

Search for this medicine at major UK pharmacy chains. These links open the retailer's own website — results depend on their current online catalogue.

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DeliveryNHS

Supply & product information

Official product databases and supply status monitoring

Shortages info

NHS Specialist Pharmacy Service (SPS)

emc product search

Discontinuations & alternatives for Flecainide

Pharmacy links redirect to the retailer's own search and do not represent real-time stock levels. emc (electronic medicines compendium) is operated by Datapharm Ltd. Shortage information sourced from NHS Specialist Pharmacy Service (SPS), sps.nhs.uk.

Codes for healthcare professionals and prescribing systems

Show details

These codes are used by healthcare IT systems and prescribers to identify this medicine.

NHS UK identifiers

SNOMED CT

12621811000001104

dm+d ID

12621811000001104

VTM (Virtual Therapeutic Moiety)

775971000

VMP (Virtual Medicinal Product)

12621811000001104

BNF code

02030200

International identifiers

ATC code — Anatomical Therapeutic Chemical (WHO)

C01BC04

Browse tools

dm+d Browser

NHSBSA medicines dictionary lookup

SNOMED CT and dm+d codes from NHS TRUD (Technology Reference data Update Distribution), licensed under the Open Government Licence v3.0. BNF codes from NHS Business Services Authority (NHSBSA). ATC codes from the WHO Collaborating Centre for Drug Statistics Methodology (whocc.no).

Active and completed clinical studies from ClinicalTrials.gov

Show details

Searching UK clinical trials...

Source: ClinicalTrials.gov, a database of the U.S. National Library of Medicine (NLM), National Institutes of Health (NIH). Data accessed via ClinicalTrials.gov API v2. Trial information is provided for research purposes and does not constitute medical advice.

Pharmacology and chemical data from DrugBank

go.drugbank.com

Key facts

Drug status

Approved

Major interactions

None known

Half-life

13 hours

Mechanism

Flecainide blocks fast inward sodium channels and slowly unbinds during diastole…

Food interactions

1 warning

Human targets

4 targets

Data: DrugBank · CC BY-NC 4.0

Pharmacokinetics at a glance

Absorption

3-4h

Oral flecainide has a T_max of 3-4h and a bioavialability of 90%.
[A186853][A186931]…

Half-life

13 hours

In healthy subjects, intravenous flecainide has an average half life of 13 hours for a single dose and 16 hours for multiple oral doses.
[A186853][L8878][L5056]…

Protein binding

40%

Flecainide is 40% bound to protein in serum, mainly to alpha-1-acid glycoprotein and minorly to serum albumin.
[A186853][L5056]

Volume of distribution

5.0-13.4L/kg

The average volume of distribution in 8 male subjects is 5.0-13.4L/kg.
[A186853]

Metabolism

20%

Flecainide is mainly metabolized to meta-O-dealkylated flecainide or the meta-O-dealkylated lactam of flecainide.
[A186853]…

Elimination

86%

Approximately 86% of a single oral dose is eliminated in the urine, with 42% as unchanged flecainide and 14% as meta-O-dealkylated flecainide,…

Clearance

4.6-12.1mL/min/kg

The average clearance of intravenous flecainide is 4.6-12.1mL/min/kg in 8 male subjects.
[A186853]…

Pharmacokinetic data: DrugBank · CC BY-NC 4.0

Status:

Approved

Investigational

Withdrawn

Small molecule

About this compound

Flecainide is a Class I anti-arrhythmic agent like [encainide] and [propafenone].[A186880] Flecainide’s development began in 1966 and was first synthesized in 1972 as an attempt to generate new anesthetics.[A186931] It is used to prevent supraventricular and ventricular arrhythmias, as well as paroxysmal atrial fibrillation and flutter.[L8878][L5056]

Flecainide was granted FDA approval on 31 October 1985.[L8875]

Properties:

solid

Avg. mass: 414.34 Da

DrugBank indication

In New Zealand and America, flecainide is indicated to prevent supraventricular arrhythmias and ventricular arrhythmias.
[L8878]
In the United States, it is also indicated to prevent paroxysmal atrial fibrillation and flutter.
[A186886][L5056]

Also known as(77)

(±)-flecainide

Flecaine

Flecainida

Flecainide

Flécaïnide

Flecainidum

N-(2-Piperidinylmethyl)-2,5-bis(2,2,2-trifluoroethoxy)benzamide

SkM1

Dosage forms(17)

Injection, solution (Intravenous; Parenteral) — 150 MG/15ML

Capsule, extended release (Oral)

Injection, solution (Parenteral) — 10 mg/ml

Tablet (Oral) — 50 mg

Tablet (Oral) — 100 mg/1

Tablet (Oral) — 150 mg/1

Tablet (Oral) — 50 mg/1

Tablet (Oral)

Molecular properties(19)

Drug interactions(964)

Known interactions with other medications. Always consult a healthcare professional.

Ivabradine

Moderate

DB09083

Ivabradine may increase the QTc-prolonging activities of Flecainide.

Check this interaction

Deferasirox

Unknown severity

DB01609

The serum concentration of Flecainide can be increased when it is combined with Deferasirox.

Check this interaction

Peginterferon alfa-2b

Unknown severity

DB00022

The serum concentration of Flecainide can be increased when it is combined with Peginterferon alfa-2b.

Check this interaction

Leflunomide

Unknown severity

DB01097

The serum concentration of Flecainide can be decreased when it is combined with Leflunomide.

Check this interaction

Teriflunomide

Unknown severity

DB08880

The serum concentration of Flecainide can be decreased when it is combined with Teriflunomide.

Check this interaction

Ethoxzolamide

Unknown severity

DB00311

The excretion of Flecainide can be decreased when combined with Ethoxzolamide.

Check this interaction

Methazolamide

Unknown severity

DB00703

The excretion of Flecainide can be decreased when combined with Methazolamide.

Check this interaction

Acetazolamide

Unknown severity

DB00819

The excretion of Flecainide can be decreased when combined with Acetazolamide.

Check this interaction

Zonisamide

Unknown severity

DB00909

The excretion of Flecainide can be decreased when combined with Zonisamide.

Check this interaction

Diclofenamide

Unknown severity

DB01144

The excretion of Flecainide can be decreased when combined with Diclofenamide.

Check this interaction

Digoxin

Unknown severity

DB00390

The serum concentration of Digoxin can be increased when it is combined with Flecainide.

Check this interaction

Metildigoxin

Unknown severity

DB13401

The serum concentration of Metildigoxin can be increased when it is combined with Flecainide.

Check this interaction

Acetyldigoxin

Unknown severity

DB13691

The serum concentration of Acetyldigoxin can be increased when it is combined with Flecainide.

Check this interaction

Atomoxetine

Moderate

DB00289

The metabolism of Atomoxetine can be decreased when combined with Flecainide.

Check this interaction

Verapamil

Unknown severity

DB00661

The risk or severity of adverse effects can be increased when Verapamil is combined with Flecainide.

Check this interaction

Tipranavir

Unknown severity

DB00932

The serum concentration of Flecainide can be increased when it is combined with Tipranavir.

Check this interaction

Amiodarone

Moderate

DB01118

The metabolism of Flecainide can be decreased when combined with Amiodarone.

Check this interaction

Boceprevir

Unknown severity

DB08873

The serum concentration of Flecainide can be increased when it is combined with Boceprevir.

Check this interaction

Amprenavir

Unknown severity

DB00701

The serum concentration of Flecainide can be increased when it is combined with Amprenavir.

Check this interaction

Fosamprenavir

Unknown severity

DB01319

The serum concentration of Flecainide can be increased when it is combined with Fosamprenavir.

Check this interaction

Mirabegron

Unknown severity

DB08893

The serum concentration of Flecainide can be increased when it is combined with Mirabegron.

Check this interaction

Sodium bicarbonate

Moderate

DB01390

Sodium bicarbonate may decrease the arrhythmogenic activities of Flecainide.

Check this interaction

Abiraterone

Moderate

DB05812

The metabolism of Flecainide can be decreased when combined with Abiraterone.

Check this interaction

Cyproterone acetate

Moderate

DB04839

The metabolism of Flecainide can be increased when combined with Cyproterone acetate.

Check this interaction

Nisoldipine

Moderate

DB00401

Nisoldipine may increase the arrhythmogenic activities of Flecainide.

Check this interaction

Acetyldigitoxin

Moderate

DB00511

Acetyldigitoxin may increase the arrhythmogenic activities of Flecainide.

Check this interaction

Magnesium sulfate

Moderate

DB00653

Magnesium sulfate may increase the arrhythmogenic activities of Flecainide.

Check this interaction

Tocainide

Moderate

DB01056

Tocainide may increase the arrhythmogenic activities of Flecainide.

Check this interaction

Deslanoside

Moderate

DB01078

Deslanoside may increase the arrhythmogenic activities of Flecainide.

Check this interaction

Carteolol

Moderate

DB00521

Flecainide may increase the arrhythmogenic activities of Carteolol.

Check this interaction

Metipranolol

Moderate

DB01214

Flecainide may increase the arrhythmogenic activities of Metipranolol.

Check this interaction

Dexpropranolol

Moderate

DB03322

Flecainide may increase the arrhythmogenic activities of Dexpropranolol.

Check this interaction

Nimesulide

Moderate

DB04743

Flecainide may increase the arrhythmogenic activities of Nimesulide.

Check this interaction

Cyclandelate

Moderate

DB04838

Flecainide may increase the arrhythmogenic activities of Cyclandelate.

Check this interaction

Seletracetam

Moderate

DB05885

Flecainide may increase the arrhythmogenic activities of Seletracetam.

Check this interaction

Nylidrin

Moderate

DB06152

Flecainide may increase the arrhythmogenic activities of Nylidrin.

Check this interaction

Dotarizine

Moderate

DB06446

Flecainide may increase the arrhythmogenic activities of Dotarizine.

Check this interaction

Xylometazoline

Moderate

DB06694

Flecainide may increase the arrhythmogenic activities of Xylometazoline.

Check this interaction

Fasudil

Moderate

DB08162

Flecainide may increase the arrhythmogenic activities of Fasudil.

Check this interaction

Agmatine

Moderate

DB08838

Flecainide may increase the arrhythmogenic activities of Agmatine.

Check this interaction

Nicorandil

Moderate

DB09220

Flecainide may increase the arrhythmogenic activities of Nicorandil.

Check this interaction

Barnidipine

Moderate

DB09227

Flecainide may increase the arrhythmogenic activities of Barnidipine.

Check this interaction

Azelnidipine

Moderate

DB09230

Flecainide may increase the arrhythmogenic activities of Azelnidipine.

Check this interaction

Cilnidipine

Moderate

DB09232

Flecainide may increase the arrhythmogenic activities of Cilnidipine.

Check this interaction

Darodipine

Moderate

DB09234

Flecainide may increase the arrhythmogenic activities of Darodipine.

Check this interaction

Niludipine

Moderate

DB09240

Flecainide may increase the arrhythmogenic activities of Niludipine.

Check this interaction

Tropisetron

Moderate

DB11699

Flecainide may increase the arrhythmogenic activities of Tropisetron.

Check this interaction

Carboxyamidotriazole

Moderate

DB11960

Flecainide may increase the arrhythmogenic activities of Carboxyamidotriazole.

Check this interaction

Naftopidil

Moderate

DB12092

Flecainide may increase the arrhythmogenic activities of Naftopidil.

Check this interaction

Vinpocetine

Moderate

DB12131

Flecainide may increase the arrhythmogenic activities of Vinpocetine.

Check this interaction

Showing 50 of 964 interactions

Food & lifestyle interactions

Advice

Take with or without food. The absorption is unaffected by food.

Toxicity & overdose

The oral LD₅₀ in rats is 1346mg/kg and in mice is 170mg/kg.
[L8923]
The subcutaneous LD₅₀ in rats is 215mg/kg and in mice is 188mg/kg.
[L8923]
The oral TDLO in women is 20mg/kg and in men is 40mg/kg/2W.
[L8923]

Patients experiencing an overdose may present with ECG abnormalities such as a lengthened PR interval, increased QRS duration, prolonged QT interval, increased amplitude of the T wave, reduced myocardial rate and contractility, hypotension, or death.
[L8878][L5056]
Treat patients with symptomatic and supportive treatment which may involve administration of inotropic agents, assisted respiration, circulatory assistance, and acidification of the urine.
[L8878][L5056]
Hemodialysis is not expected to be useful in the removal of flecainide from serum.
[A186853][L5056]

How it works

Mechanism of action

Flecainide blocks fast inward sodium channels and slowly unbinds during diastole, prolonging the refractory period of the heart.[A186931] This blockade also shortens the duration of action potentials through the Purkinjie fibers.[A186931] Flecainide also prevents delayed rectifier potassium channels from opening, lengthening the action potential through ventricular and atrial muscle fibers.[A186931] Finally, flecainide also blocks ryanodine receptor opening, reducing calcium release from sarcoplasmic reticulum, which reduces depolarization of cells.[A186931]

Pharmacodynamics

Flecainide inhibits the action of sodium and potassium ion channels in the heart, raising the threshold for depolarization and correcting arrhythmias.[A186931] Flecainide has a long duration of action, allowing for once daily dosing.[L8878] The therapeutic index is narrow.[A37372] Patients should not take this medication if there is already structural heart disease or left ventricular systolic dysfunction.[L8878]

Pharmacokinetics

How the body processes this drug — absorption, distribution, metabolism, and elimination

Absorption

Oral flecainide has a T_max of 3-4h and a bioavialability of 90%.
[A186853][A186931]
Taking flecainide with food or aluminum hydroxide antacids do not significantly affect the absorption of flecainide.
[A186853][L8878][L5056]

Half-life

In healthy subjects, intravenous flecainide has an average half life of 13 hours for a single dose and 16 hours for multiple oral doses.
[A186853][L8878][L5056]

In patients with a ventricular premature complex, flecainide has a half life of 20 hours.
[A186853][L5056]
The half life of meta-O-dealkylated flecainide, a major metabolite of flecainide, is 12.6h.
[A186853]

Protein binding

Flecainide is 40% bound to protein in serum, mainly to alpha-1-acid glycoprotein and minorly to serum albumin.
[A186853][L5056]

Volume of distribution

The average volume of distribution in 8 male subjects is 5.0-13.4L/kg.
[A186853]

Metabolism

Flecainide is mainly metabolized to meta-O-dealkylated flecainide or the meta-O-dealkylated lactam of flecainide.
[A186853]
Meta-O-dealkylated flecainide has 20% the activity of flecainide.
[A186853]
Both of these metabolites are generally detected as glucuronide or sulfate conjugates.
[A186853]
Flecainide’s metabolism involves the action of CYP2D6 and CYP1A2.
[L5056][A186931]

Route of elimination

Approximately 86% of a single oral dose is eliminated in the urine, with 42% as unchanged flecainide and 14% as meta-O-dealkylated flecainide, a similar amount of the meta-O-dealkylated lactam of flecainide, approximately 3% as an unidentified acid metabolite, and <1% as 2 other unknown metabolites.
[A186853][L8878][L5056]

5% is eliminated in the feces.
[A186853][L5056]

Clearance

The average clearance of intravenous flecainide is 4.6-12.1mL/min/kg in 8 male subjects.
[A186853]
For oral flecainide, the clearance was 4-20mL/min/kg.
[A186853]

Drug targets(4)

Proteins and enzymes this drug interacts with in the body

Sodium channel protein type 4 subunit alpha

BE0002083

SCN4A

inhibitor

Specific functionvoltage-gated sodium channel activity

Cellular location

Cell membrane

General function & pharmacology

Pore-forming subunit of Nav1.4, a voltage-gated sodium (Nav) channel that directly mediates the depolarizing phase of action potentials in excitable membranes. Navs, also called VGSCs (voltage-gated sodium channels) or VDSCs (voltage-dependent sodium channels), operate by switching between closed and open conformations depending on the voltage difference across the membrane. In the open conformation they allow Na(+) ions to selectively pass through the pore, along their electrochemical gradient.

The influx of Na+ ions provokes membrane depolarization, initiating the propagation of electrical signals throughout cells and tissues .
PMID:12766226 PMID:15318338 PMID:16890191 PMID:17898326 PMID:18690054 PMID:19347921 PMID:25707578 PMID:26659129 PMID:26700687 PMID:29992740 PMID:30190309

Highly expressed in skeletal muscles, Nav1.4 generates the action potential crucial for muscle contraction PMID:16890191 PMID:19347921 PMID:25707578 PMID:26659129 PMID:26700687

Sodium channel protein type 5 subunit alpha

BE0000197

SCN5A

inhibitor

Specific functionankyrin binding

Cellular location

Cell membrane

General function & pharmacology

Pore-forming subunit of Nav1.5, a voltage-gated sodium (Nav) channel that directly mediates the depolarizing phase of action potentials in excitable membranes. Navs, also called VGSCs (voltage-gated sodium channels) or VDSCs (voltage-dependent sodium channels), operate by switching between closed and open conformations depending on the voltage difference across the membrane. In the open conformation they allow Na(+) ions to selectively pass through the pore, along their electrochemical gradient.

The influx of Na(+) ions provokes membrane depolarization, initiating the propagation of electrical signals throughout cells and tissues .
PMID:1309946 PMID:21447824 PMID:23085483 PMID:23420830 PMID:25370050 PMID:26279430 PMID:26392562 PMID:26776555

Nav1.5 is the predominant sodium channel expressed in myocardial cells and it is responsible for the initial upstroke of the action potential in cardiac myocytes, thereby initiating the heartbeat .
PMID:11234013 PMID:11804990 PMID:12569159 PMID:1309946

Required for normal electrical conduction including formation of the infranodal ventricular conduction system and normal action potential configuration, as a result of its interaction with XIRP2 (By similarity)

Voltage-gated inwardly rectifying potassium channel KCNH2

BE0000090

KCNH2

inhibitor

Specific functiondelayed rectifier potassium channel activity

Cellular location

Cell membrane

General function & pharmacology

Pore-forming (alpha) subunit of voltage-gated inwardly rectifying potassium channel .
PMID:10219239 PMID:10753933 PMID:10790218 PMID:10837251 PMID:11997281 PMID:12063277 PMID:18559421 PMID:22314138 PMID:22359612 PMID:26363003 PMID:27916661 PMID:9230439 PMID:9351446 PMID:9765245

Channel properties are modulated by cAMP and subunit assembly .
PMID:10837251
Characterized by unusual gating kinetics by producing relatively small outward currents during membrane depolarization and large inward currents during subsequent repolarization which reflect a rapid inactivation during depolarization and quick recovery from inactivation but slow deactivation (closing) during repolarization .
PMID:10219239 PMID:10753933 PMID:10790218 PMID:10837251 PMID:11997281 PMID:12063277 PMID:18559421 PMID:22314138 PMID:22359612 PMID:26363003 PMID:27916661 PMID:9230439 PMID:9351446 PMID:9765245

Forms a stable complex with KCNE1 or KCNE2, and that this heteromultimerization regulates inward rectifier potassium channel activity PMID:10219239 PMID:9230439

Ryanodine receptor 2

BE0005295

RYR2

inhibitor

Specific functioncalcium channel activity

Cellular location

Sarcoplasmic reticulum membrane

General function & pharmacology

Cytosolic calcium-activated calcium channel that mediates the release of Ca(2+) from the sarcoplasmic reticulum into the cytosol and thereby plays a key role in triggering cardiac muscle contraction. Aberrant channel activation can lead to cardiac arrhythmia. In cardiac myocytes, calcium release is triggered by increased Ca(2+) cytosolic levels due to activation of the L-type calcium channel CACNA1C.

The calcium channel activity is modulated by formation of heterotetramers with RYR3. Required for cellular calcium ion homeostasis. Required for embryonic heart development

Metabolizing enzymes(3)

Enzymes involved in drug metabolism — important for understanding drug interactions

Enzyme activity key

substrate

inhibitor

inducer

CYP2D6Cytochrome P450 2D6

substrate

inhibitor

CYP1A2Cytochrome P450 1A2

substrate

CYP2C9Cytochrome P450 2C9

inhibitor

Transporters(2)

Proteins that transport this drug across cell membranes

ATP-dependent translocase ABCB1

BE0001032

ABCB1

substrate

Specific functionABC-type xenobiotic transporter activity

Cellular location

Cell membrane

General function & pharmacology

Translocates drugs and phospholipids across the membrane .
PMID:2897240 PMID:35970996 PMID:8898203 PMID:9038218 PMID:35507548

Catalyzes the flop of phospholipids from the cytoplasmic to the exoplasmic leaflet of the apical membrane. Participates mainly to the flop of phosphatidylcholine, phosphatidylethanolamine, beta-D-glucosylceramides and sphingomyelins .
PMID:8898203
Energy-dependent efflux pump responsible for decreased drug accumulation in multidrug-resistant cells PMID:2897240 PMID:35970996 PMID:9038218

Multidrug and toxin extrusion protein 1

BE0003657

SLC47A1

substrate

inhibitor

Specific functionantiporter activity

Cellular location

Cell membrane

General function & pharmacology

Multidrug efflux pump that functions as a H(+)/organic cation antiporter .
PMID:16330770 PMID:17509534
Plays a physiological role in the excretion of cationic compounds including endogenous metabolites, drugs, toxins through the kidney and liver, into urine and bile respectively .
PMID:16330770 PMID:17495125 PMID:17509534 PMID:17582384 PMID:18305230 PMID:19158817 PMID:21128598 PMID:24961373

Mediates the efflux of endogenous compounds such as creatinine, vitamin B1/thiamine, agmatine and estrone-3-sulfate .
PMID:16330770 PMID:17495125 PMID:17509534 PMID:17582384 PMID:18305230 PMID:19158817 PMID:21128598 PMID:24961373

May also contribute to regulate the transport of cationic compounds in testis across the blood-testis-barrier (Probable)

Carriers(2)

Proteins that carry this drug through the body

Alpha-1-acid glycoprotein 2

BE0004879

ORM2

binder

Cellular location

Secreted

General function & pharmacology

Functions as a transport protein in the blood stream. Binds various hydrophobic ligands in the interior of its beta-barrel domain. Also binds synthetic drugs and influences their distribution and availability.

Appears to function in modulating the activity of the immune system during the acute-phase reaction

Albumin

BE0000530

ALB

binder

Specific functionantioxidant activity

Cellular location

Secreted

General function & pharmacology

Binds water, Ca(2+), Na(+), K(+), fatty acids, hormones, bilirubin and drugs (Probable). Its main function is the regulation of the colloidal osmotic pressure of blood (Probable). Major zinc transporter in plasma, typically binds about 80% of all plasma zinc .
PMID:19021548
Major calcium and magnesium transporter in plasma, binds approximately 45% of circulating calcium and magnesium in plasma (By similarity).

Potentially has more than two calcium-binding sites and might additionally bind calcium in a non-specific manner (By similarity). The shared binding site between zinc and calcium at residue Asp-273 suggests a crosstalk between zinc and calcium transport in the blood (By similarity). The rank order of affinity is zinc > calcium > magnesium (By similarity).

Binds to the bacterial siderophore enterobactin and inhibits enterobactin-mediated iron uptake of E.coli from ferric transferrin, and may thereby limit the utilization of iron and growth of enteric bacteria such as E.coli .
PMID:6234017
Does not prevent iron uptake by the bacterial siderophore aerobactin PMID:6234017

Biological pathways(1)

Flecainide Action Pathway

Involved compounds

ATP,Calcium,Flecainide,Magnesium cation,Potassium cation

Scientific references(10)

Gill J.S., Mehta D., Ward D.E., Camm A.J.

Efficacy of flecainide, sotalol, and verapamil in the treatment of right ventricular tachycardia in patients without overt cardiac abnormality.

Heart

199268(10):392-397. doi: 10.1136/hrt.68.10.392

PMID: 1449923 DOI: 10.1136/hrt.68.10.392

Sakurada H., Hiyoshi Y., Tejima T., Yanase O., Tokuyasu Y., Watanabe K., Motomiya T., Sugiura M., Hiraoka M.

Short and Long-term Effects of Coronary Thrombolysis in Acute Myocardial Infarction : The treatments for myocardial infarction in acute phase.

Japanese Circulation Journal

199356(SupplementV):1409-1413. doi: 10.1253/jcj.56.supplementv_1409

PMID: 2115193 DOI: 10.1253/jcj.56.supplementv_1409

Echt D.S., Liebson P.R., Mitchell L.B., Peters R.W., Obias-Manno D., Barker A.H., Arensberg D., Baker A., Friedman L., Greene H.L., et al.

Mortality and Morbidity in Patients Receiving Encainide, Flecainide, or Placebo.

New England Journal of Medicine

1991324(12):781-788. doi: 10.1056/nejm199103213241201

PMID: 1900101 DOI: 10.1056/nejm199103213241201

Greenberg H.M., Dwyer EM Jr, Hochman J.S., Steinberg J.S., Echt D.S., Peters R.W.

Interaction of ischaemia and encainide/flecainide treatment: a proposed mechanism for the increased mortality in CAST I..

Heart

199574(6):631-635. doi: 10.1136/hrt.74.6.631

PMID: 8541168 DOI: 10.1136/hrt.74.6.631

Gasparini M., Priori S.G., Mantica M., Napolitano C., Galimberti P., Ceriotti C., Simonini S.

Flecainide Test in Brugada Syndrome: A Reproducible but Risky Tool.

Pacing and Clinical Electrophysiology

200326(1p2):338-341. doi: 10.1046/j.1460-9592.2003.00045.x

PMID: 12687841 DOI: 10.1046/j.1460-9592.2003.00045.x

Conard G.J., Ober R.E.

Metabolism of flecainide.

American Journal Cardiology

1984 Feb 2753(5):41B-51B. doi: 10.1016/0002-9149(84)90501-0

PMID: 6364769 DOI: 10.1016/0002-9149(84)90501-0

Abi Samra F.

Clinical Use of Class Ic Antiarrhythmic Drugs. Handbook of Experimental Pharmacology. 1989;:235-277.

doi: 10

1007/978-3-642-73666-7_11

PMID: 2499646 DOI: 10.1007/978-3-642-73666-7_11

Tamargo J., Le Heuzey J.Y., Mabo P.

Narrow therapeutic index drugs: a clinical pharmacological consideration to flecainide.

European Journal of Clinical Pharmacology

2015 May71(5):549-67. doi: 10.1007/s00228-015-1832-0. Epub 2015 Apr 15

PMID: 25870032 DOI: 10.1007/s00228-015-1832-0

Aliot E., Capucci A., Crijns H.J., Goette A., Tamargo J.

Twenty-five years in the making: flecainide is safe and effective for the management of atrial fibrillation.

Europace

2011 Feb13(2):161-73. doi: 10.1093/europace/euq382. Epub 2010 Dec 7

PMID: 21138930 DOI: 10.1093/europace/euq382

Andrikopoulos G.K., Pastromas S., Tzeis S.

Flecainide: Current status and perspectives in arrhythmia management.

World Journal Cardiology

2015 Feb 267(2):76-85. doi: 10.4330/wjc.v7.i2.76

PMID: 25717355 DOI: 10.4330/wjc.v7.i2.76

ATC classification(1 code)

ATC C01BC04

Affected organisms(1)

Humans and other mammals

International brands(2)

Salt forms(1)

Flecainide acetate(DBSALT000086)

Experimental properties(4)

External resources(2)

RxList Drugs.com

Commercial products(116)

Chemical identifiers

CAS, UNII, InChI Key and database cross-references

Show

Linked compound data from DrugBank Open Data (CC BY-NC 4.0)

Flecainide

DB01195

CAS number

54143-55-4

UNII (FDA)

K94FTS1806

InChI Key (molecular fingerprint)

DJBNUMBKLMJRSA-UHFFFAOYSA-N

Additional database identifiers

Drugs Product Database (DPD)

1864

ChEBI

75984

PubChem Compound

3356

PubChem Substance

46508078

KEGG Compound

C07001

KEGG Drug

D07962

ChemSpider

3239

BindingDB

50131434

PharmGKB

PA449646

Therapeutic Targets Database

DAP000518

IUPHAR

2560

Guide to Pharmacology

2560

Wikipedia

Flecainide

ChEMBL

CHEMBL652

RxCUI

4441

HUGO Gene Nomenclature Committee (HGNC)

HGNC:10591

GenAtlas

SCN4A

GeneCards

SCN4A

GenBank Gene Database

M81758

GenBank Protein Database

338213

IUPHAR

581

Guide to Pharmacology

581

UniProtKB

P35499

UniProt Accession

SCN4A_HUMAN

HUGO Gene Nomenclature Committee (HGNC)

HGNC:10593

GenAtlas

SCN5A

GeneCards

SCN5A

GenBank Gene Database

M77235

GenBank Protein Database

184039

IUPHAR

582

Guide to Pharmacology

582

UniProtKB

Q14524

UniProt Accession

SCN5A_HUMAN

HUGO Gene Nomenclature Committee (HGNC)

HGNC:6251

GenAtlas

KCNH2

GeneCards

KCNH2

GenBank Gene Database

U04270

GenBank Protein Database

487738

IUPHAR

572

Guide to Pharmacology

572

UniProtKB

Q12809

UniProt Accession

KCNH2_HUMAN

HUGO Gene Nomenclature Committee (HGNC)

HGNC:10484

GeneCards

RYR2

Guide to Pharmacology

748

UniProtKB

Q92736

UniProt Accession

RYR2_HUMAN

HUGO Gene Nomenclature Committee (HGNC)

HGNC:2625

GenAtlas

CYP2D6

GeneCards

CYP2D6

GenBank Gene Database

M20403

GenBank Protein Database

181350

Guide to Pharmacology

1329

UniProtKB

P10635

UniProt Accession

CP2D6_HUMAN

HUGO Gene Nomenclature Committee (HGNC)

HGNC:2596

GenAtlas

CYP1A2

GeneCards

CYP1A2

GenBank Gene Database

Z00036

Guide to Pharmacology

1319

UniProtKB

P05177

UniProt Accession

CP1A2_HUMAN

HUGO Gene Nomenclature Committee (HGNC)

HGNC:2623

GenAtlas

CYP2C9

GeneCards

CYP2C9

GenBank Gene Database

AY341248

Guide to Pharmacology

1326

UniProtKB

P11712

UniProt Accession

CP2C9_HUMAN

HUGO Gene Nomenclature Committee (HGNC)

HGNC:8498

GenAtlas

ORM1

GeneCards

ORM1

GenBank Gene Database

X02544

GenBank Protein Database

757907

UniProtKB

P02763

UniProt Accession

A1AG1_HUMAN

HUGO Gene Nomenclature Committee (HGNC)

HGNC:8499

GeneCards

ORM2

GenBank Gene Database

BC015964

GenBank Protein Database

16359000

UniProtKB

P19652

UniProt Accession

A1AG2_HUMAN

HUGO Gene Nomenclature Committee (HGNC)

HGNC:399

GenAtlas

ALB

GeneCards

ALB

GenBank Gene Database

V00494

GenBank Protein Database

28590

UniProtKB

P02768

UniProt Accession

ALBU_HUMAN

HUGO Gene Nomenclature Committee (HGNC)

HGNC:40

GenAtlas

ABCB1

GeneCards

ABCB1

GenBank Gene Database

M14758

GenBank Protein Database

307180

Guide to Pharmacology

768

UniProtKB

P08183

UniProt Accession

MDR1_HUMAN

HUGO Gene Nomenclature Committee (HGNC)

HGNC:25588

GeneCards

SLC47A1

GenBank Gene Database

AK001709

GenBank Protein Database

7023138

Guide to Pharmacology

1216

UniProtKB

Q96FL8

UniProt Accession

S47A1_HUMAN

International reference pricing

10 formulations

Reference pricing from DrugBank. Prices are indicative and may not reflect current UK costs.

From $0.41/tablet

To $5.75/tablet

Apo-Flecainide 50 mg Tablet

$0.41/tablet

Tambocor 50 mg Tablet

$0.60/tablet

Apo-Flecainide 100 mg Tablet

$0.83/tablet

Tambocor 100 mg Tablet

$1.19/tablet

Flecainide acetate 50 mg tablet

$1.95/tablet

Source: DrugBank. Used under CC BY-NC 4.0 academic licence for non-commercial purposes.

DrugBank citations

If you use DrugBank data in your research, please cite the following publications:

Knox C., Wilson M., Klinger C.M., et al

DrugBank 6.

0: the DrugBank Knowledgebase for 2024

Nucleic Acids Res. 2024 Jan 552(D1):D1265-D1275

PMID: 37953279

Wishart D.S., Feunang Y.D., Guo A.C., et al

DrugBank 5.

0: a major update to the DrugBank database for 2018

Nucleic Acids Res. 2017 Nov 846(D1):D1074-D1082

PMID: 29126136

Show earlier publications

Law V., Knox C., Djoumbou Y., et al

DrugBank 4.

0: shedding new light on drug metabolism

Nucleic Acids Res. 2014 Jan 142(1):D1091-7

PMID: 24203711

Knox C., Law V., Jewison T., et al

DrugBank 3.

0: a comprehensive resource for 'omics' research on drugs

Nucleic Acids Res. 2011 Jan39(Database issue):D1035-41

PMID: 21059682

Wishart D.S., Knox C., Guo A.C., et al

DrugBank: a knowledgebase for drugs, drug actions and drug targets.

Nucleic Acids Research

2008 Jan36(Database issue):D901-6

PMID: 18048412

Wishart D.S., Knox C., Guo A.C., et al

DrugBank: a comprehensive resource for in silico drug discovery and exploration.

Nucleic Acids Research

2006 Jan 134(Database issue):D668-72

PMID: 16381955

Source: go.drugbank.comCC BY-NC 4.0

Updated 27 days ago(8 Mar 2026)

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