Quinidine Kaolin

Kaolin-pectin [NE] Decreased gastrointestinal absorption of quinidine. 

There is some evidence that kaolin-pectin can reduce the absorption of quinidine and lower its serum levels. 

When 4 patients were given 30 mL of kaolin-pectin Kaopectate), after a single 100-mg oral dose of quinidine, the maximal salivary quinidine concentration was reduced by 54% and the AUC by 58%, without any effect on absorption rate. There is a correlation between salivary and serum concentrations after a single (but not repeated) doses of quinidine. This is consistent with in vitro data showing quinidine is adsorbed onto kaolin, pectin, and kaolin-pectin. Documentation appears to be limited to these two studies, but be alert for the need to increase the quinidine dosage if kaolin-pectin is used concurrently. 

Bucci AJ, Myre SA, Tan HSI, Shenouda L In vitro interactic of quinidine with kaolin and pectin. J Pharm Sci (1981) 70,999-1002. 

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