A1,
A2,
B,
C1,
C2,
D,
E,
F,
G-H,
I-K,
L,
M,
N,
O,
P1,
P2,
Q-R,
S,
T,
U-V,
W-Z
Tambocor Overdose, Contraindications and Information - Flecainide
Tambocor Overdose, Contraindications and Information - Flecainide
OVERDOSE
No specific antidote has been identified for the treatment of TAMBOCOR overdosage.
Overdoses ranging up to 8000 mg have been survived, with peak plasma flecainide
concentrations as high as 5.3 µg/mL. Untoward effects in these cases included
nausea and vomiting, convulsions, hypotension, bradycardia, syncope, extreme
widening of the QRS complex, widening of the QT interval, widening of the PR
interval, ventricular tachycardia, AV nodal block, asystole, bundle branch block,
cardiac failure, and cardiac arrest. The spectrum of events observed in fatal
cases was much the same as that seen in the non-fatal cases. Death has resulted
following ingestion of as little as 1000 mg; concomitant overdose of other drugs
and/or alcohol in many instances undoubtedly contributed to the fatal outcome.
Treatment of overdosage should be supportive and may include the following:
removal of unabsorbed drug from the gastrointestinal tract, administration of
inotropic agents or cardiac stimulants such as dopamine, dobutamine or isoproterenol;
mechanically assisted respiration; circulatory assists such as intra-aortic
balloon pumping; and transvenous pacing in the event of conduction block. Because
of the long plasma half-life of flecainide (12 to 27 hours in patients receiving
usual doses), and the possibility of markedly non-linear elimination kinetics
at very high doses, these supportive treatments may need to be continued for
extended periods of time.
Hemodialysis is not an effective means of removing flecainide from the body.
Since flecainide elimination is much slower when urine is very alkaline (pH
8 or higher), theoretically, acidification of urine to promote drug excretion
may be beneficial in overdose cases with very alkaline urine. There is no evidence
that acidification from normal urinary pH increases excretion.
CONTRAINDICATIONS
TAMBOCOR is contraindicated in patients with pre-existing second- or third-degree
AV block, or with right bundle branch block when associated with a left hemiblock
(bifascicular block), unless a pacemaker is present to sustain the cardiac rhythm
should complete heart block occur. TAMBOCOR is also contraindicated in the presence
of cardiogenic shock or known hypersensitivity to the drug.
top
