Sodium bicarbonate Quinidine

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. 

Sodium bicarbonate may be useful if torsades de pointes is because of quinidine... 

Memantine is not a major substrate for hepatic cytochrome P450 isoenzymes and has not been shown to significantly inhibit or induce these enzymes. However, memantine is partially excreted by renal tubular secretion. Thus, concomitant use of other medications that use the same renal system (i.e., triampterene, hydrochlorothiazide, digoxin, cimetidine, ranitidine, metformin, and quinidine) may affect plasma levels of both drugs (Namenda 2005). Memantine should not be used in combination with other NMDA receptor antagonists, such as amantadine or dextromethorphan, because these combinations have not been formally studied. The clearance of memantine can be reduced when the urine is alkalinized, such as with the concomitant use of sodium bicarbonate or carbonic anhy-... 

The stability of procainamide in glucose infusions may be improved by the addition of sodium bicarbonate. Patients receiving sodium chloride infusions of procainamide are prone to the risk of heart failure due to sodium load.121122 Quinidine gluconate is incompatible with intravenous infusion sets made of PVC due to drug loss by adsorption.123... 

The membrane-stabilizing activity of beta-blockers can play a major role in toxicity. Of 208 deaths in subjects who had taken beta-blockers, 206 occurred with drugs that have membrane-stabilizing activity. This quinidine-like effect can be reversed by sodium bicarbonate, which is also used to counteract the cardiotoxic effects of cyclic antidepressants, which also have membrane-stabilizing activity. 

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. 

Tricyclic antidepressant overdose includes cardiotoxicity, convulsions, and symptoms of muscarinic receptor blockade. The antidote for the quinidine-Uke cardiotoxicity of tricyclic antidepressants is sodium bicarbonate. Although physostigmine does effectively reverse anticholinergic symptoms, it can aggravate depression of cardiac conduction and can cause seizures. The answer is (J). 

In addition to these emergency measures, doctors, nurses, or paramedics may inject one or more doses of adrenalin, atropine, digitalis, lidocaine, quinidine, or sodium bicarbonate so as to obtain the desired rhythm, speed, and force of the heartbeat. 

Bicarbonate, sodium Membrane-depressant cardiotoxic drugs (tricyclic antidepressants, quinidine, etc) 1-2 mEq/kg IV bolus usually reverses cardiotoxic effects (wide QRS, hypotension). Give cautiously in heart failure (avoid sodium overload). 

Bicarbonate, sodium Membrane-depressant cardiotoxic drugs, eg, quinidine, tricyclic antidepressants... 

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