Sodium bicarbonate Flecainide

FLECAINIDE SODIUM BICARBONATE Urinary alkalinization t flecainide levels Flecainide excretion is 1 in the presence of an alkaline urine flecainide exists in predominantly non-ionic form, which is more readily reabsorbed from the renal tubules Monitor PR and BP closely... 

Oral administration of bicarbonate may decrease the absorption of ketoconazole. Increased blood levels of quinidine, flecainide, or sympatiiomimetics may occur when these agents are administered with bicarbonate There is an increased risk of crystalluria when bicarbonate is administered with the fluoroquinolones. Fbssible decreased effects of lithium, methotrexate, chlorpropamide, salicylates, and tetracyclines may occur when these drag s are administered with sodium bicarbonate. Sodium bicarbonate is not administered within 2 hours of enteric-coated drugs the protective enteric coating may disintegrate before the drug reaches the intestine. 

These principles are important in understanding additive drug combinations (e.g., quinidine and mexiletine), antagonistic combinations (e.g., flecainide and lidocaine), and potential antidotes to excess sodium channel blockade (e.g., sodium bicarbonate or propranolol). They also explain a number of clinical observations, such as why lidocaine-like drugs are relatively ineffective for supraventricular tachycardia. The type Ib drugs are fast on/off, inactivated sodium blockers atrial cells, however, have a very brief inactivated phase relative to ventricular tissue. 

Drug overdose Life-threatening flecainide intoxication in a 2-year-old toddler occurred when syringes used for oral administration were accidentally reversed, producing a fivefold flecainide overdose 3 hours after drug administration he developed a bradycardia of 50/minute and had a cardiopulmonary arrest, requiring resuscitation and adrenaline, after which the bradycardia recurred, followed by a wide-complex tachycardia that converted rapidly to a narrow-complex tachycardia after bolus intravenous adrninistration of sodium bicarbonate [60 ]. He then remained hemo-dynamicaUy stable and in sinus rhjflhm. The serum flecainide concentration was 0.7 mg/1. 

Accidental flecainide intoxication, due to a medication error, occurred in a 2-year-old toddler who was given intravenous flecainide 4.8 mg/kg/day and nadololfor persistent junctional reciprocating tachycardia [67 ]. Cardiogenic shock with absence of vital signs required emergency treatment, and ventricular tachycardia was treated with sodium bicarbonate recovery was uneventful. The serum flecainide concentration was 0.67 mg/1. 

QTc intervals. Two hours postingestion the flecainide level was 1.4mg/L. After the administration of sodium bicarbonate a dramatic improvement in terminal R wave and bifascicular block was observed [26]. 

ATP is ineffective to slow or stop the flecainide-induced tachycardia. The administration of 8.4% sodium bicarbonate should be the preferred management in this clinical setting [27]. 

A 72-year-old woman, treated with flecainide and haloperidol, presented with breathlessness due to regular tachycardia with wide QRS complex. The ECG showed a regular monomorphic tachycardia at ISObpm, no apparent P wave, QRS duration of 240 ms with a left bxmdle branch block. An intravenous bolus of 10 mg ATP was administered. However, it turned out to be ineffective. The diagnosis of tachycardia induced by flecainide overdose was considered and treatment with 8.4% sodium bicarbonate was initiated. The sodium bicarbonate infusion caused immediate narrowing of the patienPs QRS and the ECG showed sinus rhythm. Blood samples confirmed flecainide overdose [27]. 

An 82-year-old woman, after ingesting 400 mg of flecainide, developed bradycardia, hypotension, and complete heart block. Treatment with sodium bicarbonate, atropine, calcium gluconate, and dopamine was introduce... 

Jang DH, Hoffinan RS, Nelson LS. A case of near-fatal flecainide overdose in a neonate successfully treated with sodium bicarbonate. J Emerg Med 2013 44(4) 781. ... 

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