Quinidine with thiazide diuretics

Quinidine and thiazide diuretics can both enhance the toxicity of digitalis. The action of quini-dine is attributed to phtirmacokinetic mechanisms, especially inhibition of its clearance. The plasma concentration of digoxin predictably increases when quinidine is added. The enhancement of digitalis toxicity by thiazides is due to a pharmacodynamic mechanism, namely, the action of these diuretics to reduce extracellular potassium. Sulfasalazine decreases plasma levels of digitalis by interfering with gut absorption of the drug. The answer is (D). 

Clinically important, potentially hazardous interactions with alprazolam, amiodarone, amphotericin B, arbutamine, bendroflumethiazide, benzthiazide, bisacodyl, bumetanide, carbimazole, chlorothiazide, chlorthalidone, cholestyramine, clarithromycin, conivaptan, cyclosporine, cyclothiazide, dan-shen, demeclocycline, devil s claw, dexmedetomidine, doxycycline, erythromycin, esomeprazole, ethacrynic acid, flunisolide, furosemide, ginseng, glycopyrrolate, glycopyrronium, hawthorn (fruit, leaf, flower extract), horsetail, hydrochlorothiazide, hydroflumethiazide, indapamide, licorice, lopinavir, mepenzolate, methyclothiazide, metolazone, minocycline, mistletoe, oxprenolol, oxytetracycline, paroxetine, phenylbutazone, polythiazide, propafenone, propantheline, quinethazone, quinidine, rabeprazole, rifampin, roxithromycin, sarsaparilla, senna, Siberian ginseng, squill, St John s wort, telithromycin, teriparatide, tetracycline, thiazide diuretics, tolvaptan, trichlormethiazide, verapamil... 

Clinically important, potentially hazardous interactions with alcohol, amiodarone, anticholinergics, antihistamines, barbituates, cisapride, dofetilide, doxazosin, erythromycin, guanethidine, hydralazine, levodopa, lithium, methyldopa, metoclopramide, moxifloxacin, piperazine, quinidine, sibutramine, sotalol, thiazide diuretics, thioridazine... 

The drug most commonly used in clinical practice that can produce immune thrombocytopenic purpura is heparin. Other examples are sulfonamides, thiazide diuretics, chlorpropamide, quinidine, and gold. These types of immune thrombocytopenic purpura are reversed when the drug is withdrawn. Molecular mechanisms for the formation of specific drug-dependent antibodies appear to be very similar. The glycoproteins on the platelet surface interact with the drugs to form neo-epitopes. Subsequent... 

Increased risk of toxicity with drugs that alter serum electrolytes (potassium -depleting diuretics, corticosteroids, thiazide and loop diuretics, amphotericin B, quinidine, amiodarone). Blockers of p adrenergic receptors, calcium channels, or acetylcholinesterase increase risk of complete AV block. Drugs which alter Gl absorption may alter bioavallabillty. 

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