Flecainide

414.34

414.34

200-659-6

719273

DTXSID8023054

C01BC04|C - Cardiovascular system

59.6

3.8

Solid

1.286 g/cm3

145-147 °C

434.9°C at 760 mmHg

9℃

3.24e-02 g/L

Refrigerator

9.3None

9.3

192.2 Ų [M+H]+ [CCS Type: TW, Method: Major Mix IMS/Tof Calibration Kit (Waters)]

III

6.1(b)

3249

1

11-23/24/25-39/23/24/25

7-16-36/37-45

F,T

P210-P260-P280-P301 + P310-P311

H225-H301 + H311 + H331-H370

|Warning|H302 (100%): Harmful if swallowed [Warning Acute toxicity, oral]|P201, P202, P264, P270, P281, P301+P312, P308+P313, P330, P405, and P501|The GHS information provided by 1 company from 1 notification to the ECHA C&L Inventory.

The oral LD50 in rats is 1346mg/kg and in mice is 170mg/kg. The subcutaneous LD50 in rats is 215mg/kg and in mice is 188mg/kg. The oral TDLO in women is 20mg/kg and in men is 40mg/kg/2W. 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. Treat patients with symptomatic and supportive treatment which may involve administration of inotropic agents, assisted respiration, circulatory assistance, and acidification of the urine. Hemodialysis is not expected to be useful in the removal of flecainide from serum.

In clinical trials, flecainide was associated with a low rate of serum aminotransferase and alkaline phosphatase elevations. Despite wide scale use, flecainide has only rarely been linked to cases of clinically apparent liver injury. The typical presentation is with a cholestatic hepatitis arising within 1 to 6 weeks of starting flecainide. In addition, instances of acute hepatic injury arising within 1 to 3 days of starting flecainide with marked, but short lived elevations in serum aminotransferase levels and minimal increases in alkaline phosphatase have been published, but may actually represent acute worsening of congestive heart failure and ischemic hepatitis due to the proarrhythmic effects of flecainide. In all instances, the liver injury was self limited. Immunoallergic and autoimmune features were not present.

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

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

Flecainide is an oral antiarrhythmic agent that has been in use for several decades. Long term flecainide therapy is associated with a low rate of serum enzyme elevations and is a very rare cause of clinically apparent acute liver injury.

Antiarrhythmic Agents

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

A class of drugs that inhibit the activation of VOLTAGE-GATED SODIUM CHANNELS. (See all compounds classified as Voltage-Gated Sodium Channel Blockers.)|Agents used for the treatment or prevention of cardiac arrhythmias. They may affect the polarization-repolarization phase of the action potential, its excitability or refractoriness, or impulse conduction or membrane responsiveness within cardiac fibers. Anti-arrhythmia agents are often classed into four main groups according to their mechanism of action: sodium channel blockade, beta-adrenergic blockade, repolarization prolongation, or calcium channel blockade. (See all compounds classified as Anti-Arrhythmia Agents.)

Oral flecainide has a T_max of 3-4h and a bioavialability of 90%. Taking flecainide with food or aluminum hydroxide antacids do not significantly affect the absorption of flecainide.|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. 5% is eliminated in the feces.|The average volume of distribution in 8 male subjects is 5.0-13.4L/kg.|The average clearance of intravenous flecainide is 4.6-12.1mL/min/kg in 8 male subjects. For oral flecainide, the clearance was 4-20mL/min/kg.

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

In healthy subjects, intravenous flecainide has an average half life of 13 hours for a single dose and 16 hours for multiple oral doses. In patients with a ventricular premature complex, flecainide has a half life of 20 hours. The half life of meta-O-dealkylated flecainide, a major metabolite of flecainide, is 12.6h.

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

Apocard

Human Drugs -> FDA Approved Drug Products with Therapeutic Equivalence Evaluations (Orange Book) -> Active Ingredients|Pharmaceuticals