Flecainide
Flecainide. Class IC antiarrhythmic — strong Na+ channel blocker with slow dissociation. "Pill-in-pocket" approach for paroxysmal atrial… Oral half-life 9.5 h.
Class IC antiarrhythmic — strong Na+ channel blocker with slow dissociation. "Pill-in-pocket" approach for paroxysmal atrial fibrillation in structurally normal hearts. Pro-arrhythmic in ischemic heart disease (CAST trial 1989) — contraindicated post-MI.
PK: F 0.81 is verbatim AND is the correct member of a stated triplet — "The mean absolute bioavailability was 98%, 78% and 81% for the rectal and oral solutions and the tablet" — the tablet value, correctly chosen. The cleanest sourcing in its group. V 350 L was 5.0 L/kg scaled to 70 kg, a round template that UNDERSTATES the measured intravenous volume of 7.5 L/kg by a third; half-life 14 h came from a review and the primary gives 9.5 h. ka 0.7 appears in no flecainide abstract; two candidate origins are logged as hypotheses rather than findings — it is either the RECTAL time to peak (0.67 h) from its own paper, or DIGOXIN literature absorption rate, digoxin being the other compound in the same audit group. UNUSUALLY GOOD NEWS: CYP2D6 does not matter here — "The CYP2D6 polymorphism did not appear to influence flecainide disposition kinetics or electrocardiographic effects at steady state" — so a scalar bioavailability IS defensible for this drug, unlike most of its class.
Pharmacokinetics
- Oral — t½ 9.5 h · F 81% · Vd 525 L
Sources: PMID:6437721, PMID:3141098, PMID:12189358