Disopyramide

Disopyr mide. Disopyramide phosphate, a phenylacetamide analogue, is a racemic mixture. The dmg can be adininistered po or iv and is useful in the treatment of ventricular and supraventricular arrhythmias (1,2). After po administration, absorption is rapid and nearly complete (83%). Binding to plasma protein is concentration-dependent (35—95%), but at therapeutic concentrations of 2—4 lg/mL, about 50% is protein-bound. Peak plasma concentrations are achieved in 0.5—3 h. The dmg is metabolized in the fiver to a mono-AJ-dealkylated product that has antiarrhythmic activity. The elimination half-life of the dmg is 4—10 h. About 80% of the dose is excreted by the kidneys, 50% is unchanged and 50% as metabolites 15% is excreted into the bile (1,2). 

Introducing yet more structural complexity into the amine component leads to the antiarrhythmic agent disobutamide (24). Disobutamide is structurally related to disopyramide but... 

Isopropamide iodide Diisopropylaminoethyl chloride Disopyramide phosphate Propantheline bromide Diketene Ketazolam Pyrithyidione... 

Ryegonovin - Methylergonovine maleete Rynecrom - Cromolyn sodium Rythmical - Disopyramide phosphate Rythmoden - Disopyramide phosphate Rythmodul Disopyramide phosphate Rytmil - Bisacodyl Rytmilen - Disopyramide phosphate Rytmonorm - Propafenone HCI... 

Armstrong and Jin [15] reported the separation of several hydrophobic isomers (including (l-ferrocenylethyl)thiophenol, 1 -benzylnornicotine, mephenytoin and disopyramide) by cyclodextrins as chiral selectors. A wide variety of crown ethers have been synthesized for application in enantioselective liquid membrane separation, such as binaphthyl-, biphenanthryl-, helicene-, tetrahydrofuran and cyclohex-anediol-based crown ethers [16-20]. Brice and Pirkle [7] give a comprehensive overview of the characteristics and performance of the various crown ethers used as chiral selectors in liquid membrane separation. 

Disopyramide anti-airhythmic, S(+)-isomer more sb ongly protein bound... 

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 antiemetics and antivertigo drug may have additive effects when used with alcohol and other CNS depressants such as sedatives, hypnotics, antianxiety drugp, opiates, and antidepressants. There may be additive anticholinergic effects (see Chap. 25) when administered with drag s that have anticholinergic activity such as the antihistamines, antidepressants, pheno-thiazines, and disopyramide The antacids decrease absorption of the antiemetics. 

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. 

ADMINISTERING DISOPYRAMIDE. Because of the cholinergic blocking effects of disopyramide (see Chap. 25), urinary retention may occur. The nurse monitors the urinary output closely, especially during the initial period of therapy. If the patient s intake is sufficient but the output is low, the lower abdomen is... 

Dryness of the mouth and throat caused by die cholinergic blocking action of this drug also may occur. The nurse provides an adequate amount of fluid and instructs die patient to take frequent sips of water to relieve diis problem. In addition, postural hypotension may occur during die first few weeks of disopyramide therapy. The patient is advised to make position changes slowly. In some instances, the patient may require assistance in getting out of the bed or chair. 

Cj H7N 140-29-4) see Azatadine Dicycloverine Disopyramide Ethoheptazine Isoaminile Levocabastine Mephenytoin Methylphenidate Methylphenobarbital Milnacipran hydrochloride Oxeladin Pentapiperide Pentoxyverine Pethidine Phenglutarimide Pheniramine Phenobarbital Tolazoline Triamterene Valethamate bromide 1 -benzy l-4-cyanopiperidine (C]3H 9N2 62778-37-4) see Ketanserin... 

C5H4CIN 109-09-1) see Brompheniramine Chlorphenamine Disopyramide Methylphenidate Pheniramine Pyrithione zinc Rosiglitazone Trazodone 4-chloropyridine... 

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