Quinidine Disopyramide

D Amiodarone is the best option. Disopyramide, quinidine, and sotalol all have negative inotropic effects, which may exacerbate his CHF. Lidocaine may be given in patients with CHF, but it is only administered IV due to its low bioavailability and is not suitable for long-term maintenance. 

I a With prolongation of action potential Quinidine, Procainamide, Disopyramide, Ajmaline, Prajmaline... 

Further class IA drugs include the open state blockers procainamide and disopyramide with electrophysiolog-ical effects similar to those of quinidine procainamide lacks the antimuscarinic and antiadrenergic effects. Characteristic side effects of procainamide are hypotension and immunological disorders. 

Amantadine is used cautiously in patients with seizure disorders, psychiatric problems, renal impairment, and cardiac disease. Amantadine is a Pregnancy Category B drug and is used cautiously during pregnancy and lactation. Concurrent use of antihistamines, phenothiazines, tricyclic antidepressants, disopyramide, and quinidine may increase the anticholinergic effects (dry mouth, blurred vision, constipation) of amantadine... 

The drugp disopyramide, procainamide, and quinidine are examples of class I-A drugs. Quinidine depresses... 

All antiarrhythmic dra are used cautiously in patients with renal or hepatic disease. When renal or hepatic dysfunction is present, a dosage reduction may be necessary. All patients should be observed for renal and hepatic dysfunction. Quinidine and procainamide are used cautiously in patients with CHF. Disopyramide is used cautiously in patients with CHF, myasthenia gravis, or glaucoma, and in men with prostate enlargement. Bretylium is used cautiously in patients with digitalis toxicity because the initial release of norepinephrine with digitalis toxicity may exacerbate arrhythmias and symptoms of toxicity. Verapamil is used cautiously in patients with a history of serious ventricular arrhythmias or CHF. Electrolyte disturbances such as hypokalemia, hyperkalemia, or hypomagnesemia may alter the effects of the antiarrhythmic dru . Electrolytes are monitored frequently and imbalances corrected as soon as possible... 

When two antiarrhythmic dragp are administered concurrently the patient may experience additive effects and is at increased risk for drug toxicity. When quinidine and procainamide are administered with digitalis, tiie risk of digitalis toxicity is increased. Hiarmacologic effects of procainamide may be increased when procainamide is administered with quinidine When quinidine is administered with the barbiturates or cimetidine, quinidine serum levels may be increased. When quinidine is administered with verapamil, there is an increased risk of hypotensive effects. When quinidine is administered with disopyramide, there is an increased risk of increased disopyramide blood levels and/or decreased serum quinidine levels. 

ADM INI STERI NG DISOPYRAMID E Disopyramide is administered to tiie patient with a full glass of water either 1 hour before or 2 hours after meals. If patients are receiving procainamide or quinidine tiie manufacturer suggests that disopyramide therapy not be started for 6 to 12 hours after tiie last dose of quinidine and 3 to 6 hours after tiie last dose of procainamide When tiie patient is to switch from taking tiie regular capsules to taking extended-release capsules, 6 hours should lapse after tiie last capsule before therapy is begun with tiie extended-release capsules. 

Procainamide, quinidine, quinine, disopyramide, phenytoin, and (i-adrenergic blockers, calcium channel blockers... 

Concurrent antiarrhythmic agents Concurrent antiarrhythmic agents may produce enhanced prolongation of conduction or depression of contractility and hypotension, especially in patients with cardiac decompensation. Reserve concurrent use of procainamide with other Class lA antiarrhythmic agents (eg, quinidine, disopyramide) for patients with serious arrhythmias unresponsive to a single drug and use only if close observation is possible. 

Transfer to disopyramide Use the regular maintenance schedule, without a loading dose, 6 to 12 hours after the last dose of quinidine or 3 to 6 hours after the last dose of procainamide. Where withdrawal of quinidine or procainamide is likely to produce life-threatening arrhythmias, consider hospitalization. 

Drugs that may affect disopyramide include antiarrhythmics, beta blockers, cisapride, clarithromycin, erythromycin, fluoroquinolones, hydantoins, quinidine, thioridazine, rifampin, verapamil, and ziprasidone. Drugs that may be affected by disopyramide include quinidine, anticoagulants, and digoxin. 

Drugs that may affect amiodarone include hydantoins, cholestyramine, fluoroquinolones, rifamycins, ritonavir, and cimetidine. Drugs that may be affected by amiodarone include anticoagulants, beta-blockers, calcium channel blockers, cyclosporine, dextromethorphan, digoxin, disopyramide, fentanyl, flecainide, hydantoins, lidocaine, methotrexate, procainamide, quinidine, and theophylline. Drug/Lab test interactions Amiodarone alters the results of thyroid function tests, causing an increase in serum T4 and serum reverse T3 levels and a decline in... 

Acetaminophen Amiodarone Carbamazepine Cardiac glycosides Corticosteroids Dicumarol Disopyramide Doxycycline Estrogens Haloperidol Methadone Metyrapone Mexiletine Oral contraceptives Quinidine Theophylline Valproic acid Cyclosporine Dopamine Furosemide Levodopa Levonorgestrel Mebendazole Nondepolarizing muscle relaxant Phenothiazines Sulfonylureas... 

Drugs that may be affected by itraconazole include alfentanil, almotriptan, alprazolam, amphotericin B, aripiprazole, benzodiazepines, buspirone, busulfan, calcium blockers, carbamazepine, cilostazol, cisapride, corticosteroids, cyclosporine, digoxin, disopyramide, docetaxel, dofetilide, eletriptan, epierenone, ergot alkaloids, haloperidol, HMG-CoA reductase inhibitors, hydantoins (phenytoin), hypoglycemic agents, oral midazolam, phosphodiesterase type 5 inhibitors, pimozide, polyenes, protease inhibitors, quinidine, rifamycins, sirolimus, tacrolimus, tolterodine, triazolam, trimetrexate, vinca alkaloids, warfarin, and zolpidem. 

Rifampin is known to induce the hepatic microsomal enzymes that metabolize various drugs such as acetaminophen, oral anticoagulants, barbiturates, benzodiazepines, beta blockers, chloramphenicol, clofibrate, oral contraceptives, corticosteroids, cyclosporine, disopyramide, estrogens, hydantoins, mexiletine, quinidine, sulfones, sulfonylureas, theophyllines, tocainide, verapamil, digoxin, enalapril, morphine, nifedipine, ondansetron, progestins, protease inhibitors, buspirone, delavirdine, doxycycline, fluoroquinolones, losartan, macrolides, sulfonylureas, tacrolimus, thyroid hormones, TCAs, zolpidem, zidovudine, and ketoconazole. The therapeutic effects of these drugs may be decreased. 

Cardiovascular Acetyldigosin, ajmaline, amiodarone, aprindine, bepridil, bezaflbrate, captopril, dinepazide, clopidogrel, coumarins, diazoxide, digoxin, dipyridamole, disopyramide, doxazosin, enalapril, flurbiprofen, fur-oxemide, hydralazine, lisinopril methyldopa, metolazone, nifedipine, phenindione, procainamide, propanolol, propafenone, quinidine, ramapril, spironolactone, thiazide diuretics, ticlopidine, vesnarinone... 

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