flecainide

Brand: Tambocor

⚠ BBW Prototype Drug

Drug Class: antiarrhythmic (Class IC)

Drug Family: antiarrhythmic

Subclass: sodium channel blocker (potent)

Organ Systems: cardiovascular

Mechanism of Action

Potent sodium channel blockade slowing conduction velocity throughout the heart; most effective Class IC agent; no effect on refractoriness.

fast sodium channels (open/inactivated state)

Drug / Agent	Mechanism	Severity
amiodarone	increases flecainide levels	major
CYP2D6 inhibitors	increased flecainide exposure	moderate
digoxin	increases digoxin level 15-25%	moderate

CONTRAINDICATED post-MI or structural heart disease (CAST trial)
Used only in structurally normal hearts
Pill-in-pocket approach for paroxysmal AF (single oral dose 200-300 mg during AF episode)
Must block AV node first if used in AF (beta-blocker or CCB) to prevent 1:1 flutter conduction

CAST trial: flecainide increased mortality post-MI — class effect for Class IC agents in structural heart disease
Pill-in-pocket strategy: single high dose taken at AF onset — effective outpatient cardioversion
1:1 flutter: flecainide slows atrial flutter rate from 300 to 240 bpm but AV node may conduct all impulses

Pregnancy avoid

Lactation avoid

Renal Adjustment Required

Hepatic Adjustment Required

TDM Not required

Cross-referenced clinical concepts — click any term to see all content where it appears.