Cardiovascular agents quinidine

A. Cardiovascular. Anticholinergic effects may produce tachycardia. Alpha-adrenergic blockade may cause orthostatic hypotension. With very large overdoses of some agents, quinidine-llke membrane-depressant effects on the heart may occur. Many agents can cause QT prolongation and torsade de pointes (see p 14). 

Cardiovascular agents - The metabolism of guinidine, a naturally occurring alkaloid with antiarrhythmic properties, was studied in man as the gluconate salt. Metabolites isolated from urine were found to be oxygenated on either the quinoline or guinuclidine portions of the molecule uncharacterized polyoxygenated derivatives were also found. Commercially available supplies of quinidine consistently contained 10 to 30 percent of an impurity. 

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