Heart failure drug poses potassium problems.

Harvard Heart Letter, December, 2004

When using "the water pill" spironolactone, watch your potassium intake and check your levels.

The old adage "many hands make light work" applies to drug therapy for heart failure -- many medications help lighten the burden cast by this common condition. Since the publication of a landmark trial in 1999, one drug that is being used more and more for people with advanced heart failure is spironolactone (spear-on-oh-LACK-tone), a potassium-sparing diuretic. Sold under the brand name Aldactone, this drug helps the kidneys get rid of water. Yet unlike most other diuretics, which indiscriminately flush out minerals along with water, spironolactone causes the kidneys to hold onto potassium.

Normally, that's not a bad thing. Most Americans get far too little of...