Flecainide was originally sold under a brand name Tambocor^® (made by 3M pharmaceuticals). Flecainide went off-patent on February 10^th, 2004, and is nowadays available under a trade list Almarytm^®, Apocard^®, Ecrinal^®, & Flécaine^®. These are besides available generically.

Uses
Flecainide is utilized in the professional assistance of numbers of types of supraventricular tachycardias, including AV nodal reciprocating tachycardia (AVNRT) and Wolff-Parkinson-White syndrome (WPW). This is because of the action of tambocor on the His-Purkinje system.

It besides has limited have in the coarse of action of certain forms of ventricular tachycardia (VT). Particularly, tambocor has been utile in the coarse of action of ventricular tachycardias that are non in the setting of an intense ischaemic event. It has utilise in the coarse of action of perfect ventricular outflow tract (RVOT) tachycardia^Single & inside the suppression of arrhythmias in arrhythmogenic right ventricular dysplasia (ARVD)². Nevertheless, studies use at times shown an increased mortality once tambocor is utilized to suppress ventricular extrasystoles in the setting of acute myocardial infarction.^3,4

Within souls suspected of havings a Brugada syndrome, a administration of tambocor could aid reveal the ECG findings that are characteristic of the disease run. This can assist produce a diagnosing of the disease around ambiguous events.⁵

Flecainide has been introduced into a professional assistance of arrhythmias in the pediatric population.

Dosing
A dosing of tambocor is varied, considerately manufactured to the single's more medications & comorbid conditions you said it it will affect a metabolism of tambocor. People by owning important nephritic impairment can expect measure of a plasma level of tambocor to assure that a drug level remains inside the curative range (explorer: that toxic levels don't occur). Additionally, moo drug levels can be saught for the coarse of action of benign arrhythmias, to lower the risk of causing a toxic burden of the drug. Whilst utilized in a paediatric people, the dose of tambocor can be adjusted to the single's body surface area.

Given a variable half life of tambocor & a characteristic QT prolongatiin on ECG elicited around tambocor even toxicity, starting tambocor or changing a level of the drug is done under telemetry monitoring (preferably in the hospital telemetry unit) until a steadily state plasma level has been achieved, occasionally 3 to 5 years when the dose has been increased.

For the coarse of action of supraventricular tachycardias and paroxysmal atrial fibrillation or flutter in individuals while forgoing important structural heart condition, the starting dose of L mg twice the day can be appropriate. the dose can be increased (it used to be that a steadily state level has been reached) whenever breakthrough arrhythmias occur.

For the coarse of action of life-threatening ventricular arrhythmias (explorer: ventricular tachycardia), the starting dose of Centred mg twice a day can be appropriate. When sustaining the coarse of action of benign arrhythmias, a dose of tambocor given for the coarse of action of life-threatening ventricular arrhythmias should non exist as increased until a steadily state has been achieved.

Mechanism of action
Flecainide works by blocking a Nav1.Fin na channel in the heart, stimulating prolongation of the cardiac action potential.⁶ This thereby slows conductivity of a electrical impulse in the heart. A greatest burden is on the His-Purkinje system and ventricular myocardium. the symptom of tambocor on the ventricular myocardium induces reduced contractility of the muscle, which leads to a decrease in the ejection fraction.

A symptom of tambocor on a na trend lines of the heart increases when the pulse increases.^Septenary This is referred to as have-dependance. This means that tambocor is possibly further utile to break the tachyarrhythmia (because it has increased symptom in the period of the convenient pulse rate) than to halt a tachyarrhythmia from either occurring (because of its lowered effectiveness when you took slower pulse).

Metabolism and drug interactions
Flecainide has high bioavailability after an oral dose^Octet, meaning that virtually all of a drug that is ingested may enter the systemic blood stream. Peak blood serum concentrations may be seen 1 to 6 hours when uptake of an unwritten dose. When a plasma half life is about Twenty hours, these are quite variable, & may range from either 12 to 27 hours^Nine. within the period of unwritten loading by using tambocor, the steadily state equilibrium is usually achieved in Three to Five years.

A majority of tambocor is eliminated per kidneys, with a remainder metabolised per cytochrome P450 IID6 isoenzyme in the liver.¹⁰ So, alterations around nephritic work or even piddle pH might greatly affect a elimination of tambocor, every bit supplementary is eliminated per hepatic route.

Because of the dual elimination routes of tambocor & it's tendency to decrease myocardial contractility¹¹, flecainide interacts by using many pharmaceutic & potty potentiate a results of more myocardial downer & AV node blocking professionals. Additionally, tambocor even may decrease a metabolism or elimination of numbers of (but not everthing) offices that have a cytochrome P450 enzyme system.

a fully listings of drug interactions using tambocor may be found from either the manufacturer. A select few significant drug interactions by having tambocor include: Alcohol - may farther depress normal heart work. Amiodarone - inhibits cytochrome P450 IID6 and may increase tambocor levels Cimetidine - increases flecainide levels by 30% & half-life by 10% Digoxin - may increase lanoxin levels Paroxetine - increased effect of two doses. Propafenone - increased effect of each doses & increased chance of toxicity. Quinidine - inhibits cytochrome P450 IID6 and may increase tambocor levels

Serious adverse reactions
Effects of the medical learn called the Cardiac Arrhythmia Suppression Test (CAST) demonstrated that patients by having structural cardiopathy (like a history of MI (heart attack), or even LV Dysfuction) & too patients sustaining ventricular arrythmias, should does'nt choose this drug. Within patients by having these kindthe cardiopathy, tambocor actually increases a risk of suffering a calamitous arrythmia.

A dose could want to become adjusted inside certain clinical scenarios. When using tons more antiarrhythmic agents, there is a risk of proarrhythmia associated sustaining a apply of tambocor. This chance is probably increased once tambocor is co-administered sustaining more class Ic antiarrhythmics, like encainide. A chance of proarrhythmia may also exist as increased by hypokalemia.¹² A chance of proarrhythmia is non necessarily associated by using a length of period an personal is ingesting tambocor, & shells late proarrhythmia keep close at hand been reported.^{Long dozen} Because of a role of each a liver & a kidneys inside the elimination of tambocor even, the dosing of tambocor could want to become adjusted in souls world health organization evolve either liver failure or kidney failure.

Because of the veto inotropic results of tambocor^Eleven, it should become utilized using caution within souls by having depressed ejection fraction, and will worsen congestive heart failure in these individuals.

When by having everthing class I personally antiarrhythmic agents, Flecainide increases the capture thresholds of pacemakers.¹⁴ So, capture thresholds should exist as remeasured around souls by using pacemakers when a steady-state tambocor dose is changed.

Toxicity
Due to the narrow alterative stock of tambocor, dr. should exist as alert for signs of toxicity prior to life-serious arrhythmias occur. Whlie a toxic results of tambocor come closely related the plasma levels of the drug^Xv, these are unfeasible to prevent a plasma concentration inside an human regularly.

Signs of tambocor toxicity include marked prolongation of the PR interval & widening of the QRS duration on the skin-deep ECG. There can be signs & consequences attributable to open heart failure secondary to sudden decreased myocardial contractility.

Treatment
Professional assistance of tambocor toxicity involves increasing a excretion of tambocor, blocking it's results in the heart, & (seldom) institution of cardiovascular trend lines to stay away from at hand deadly arrhythmias. Modalities that will have profits include administration of the beta-sympathomimetic professional^Fifteen, & administration of the na machine load^Fifteen (typically in the form of hypertonic sodium bicarbonate). Placing the single in cardiorespiratory bypass trend lines several exist as necessary sequentially to temporarily obviate a want for a pulsating heart & to increase blood flow to the liver^16,17.

Long term effects
within the long term, Flecainide seems to become safe in patients using the sound heart by having there is no signs of Left ventricular hypertrophy, ischemic heart disease or heart failure.