Potassium chloride gastrointestinal effects

Sustained release preparations of potassium chloride have been widely used to overcome the gastrointestinal side effects following medication with enteric coated tablets. Such formulation techniques delay the rate of absorption and produce a slow release of potassium chloride during the passage through the gastrointestinal tract [1,2]. 

The main adverse effects of oral potassium salts are hyperkalemia, particularly when they are used in combination with potassium-sparing drugs, such as spironolactone and ACE inhibitors, and gastrointestinal ulceration and perforation, particularly with modified-release formulations. The problems surrounding enteric-coated potassium chloride tablets are unresolved. Despite recommendations that they be withdrawn, some are still available. The risks seem to be less with slow-release potassium chloride tablets. 

McMahon FG, Ryan JR, Akdamar K, Ertan A. Effect of potassium chloride supplements on upper gastrointestinal mucosa. Clin Pharmacol Ther 1984 35 852-855. 

Similar to the other high-ceiling diuretics, ethacrynic acid inhibits the NaVKV2CI symporter in the ascending limb of the loop of Henie to promote a marked diuresis. Sodium, chloride, potassium, and calcium excretion are increased following oral or intravenous administration of ethacrynic acid. Oral administration of ethacrynic acid results in diuresis within 1 hour and a duration of action of 6 to 8 hours. Toxicity induced by ethacrynic acid is similar to that induced by furosemide and bumetanide. Ethacrynic acid is not widely used, however, because it induces a greater incidence of ototoxicity and more serious gastrointestinal effects than those of furosemide or bumetanide. 

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