Furosemide Colestipol

ANION EXCHANGE RESINS DIURETICS Both colestipol and colestyramine markedly 1 levels of loop diuretics and thiazides Colestipol and colestyramine bind diuretics in the intestine Give the anion exchange resin 3 hours after furosemide and 4 hours after thiazides (although the effect of hydrochlorothiazide may still be 1 by colestyramine)... 

Colestyramine and colestipol markedly reduce the absorption and diuretic effects of furosemide. 

In 6 healthy subjects colestyramine 8 g reduced the absorption of a single 40-mg dose of furosemide by 95%. The 4-hour diuretic response was reduced by 77% (urinary output reduced from 1510 to 350 mL). Colestipol 10 g reduced the furosemide absorption by 80% and the 4-hour diuretic response by 58% (urinary output reduced from 1510 to 630 mL). ... 

Both colestyramine and colestipol are anionic exchange resins, which can bind with furosemide within the gut, thereby reducing its absorption and... 

An established interaction, although direct evidence seems to be limited to this study. The absorption of furosemide is relatively rapid so that giving it 2 to 3 hours before either the colestyramine or colestipol should be an effective way of overcoming this interaction. This needs confirmation. Note that it is normally recommended that other drugs are given 1 hour before or 4 to 6 hours after colestyramine and 1 hour before or 4 hours after colestipol. 

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