Drospirenone is an antimineralocorticoid with potassium-sparing properties, though in most cases no increase of potassium levels is to be expected. In women with mild or moderate chronic kidney disease, or in combination with chronic daily use of other potassium-sparing medications (ACE inhibitors, angiotensin II receptor antagonists, potassium-sparing diuretics, heparin, antimineralocorticoids, or nonsteroidal anti-inflammatory drugs), a potassium level should be checked after two weeks of use to test for hyperkalemia. Persistent hyperkalemia that required discontinuation occurred in 2 out of around 1,000 women (0.2%) with 4 mg/day drospirenone alone in clinical trials.