Not Medical Advice: A white oval pill (or elliptical-shaped pill) imprinted with 58 81 on one side and a V on the other side is spironolactone 50mg, an aldosterone receptor antagonist and potassium-sparing diuretic used in treating heart failure, high blood pressure, edema, hirsutism, acne, and other conditions. It is commonly marketed under the brand name Aldactone.
In treating edema, spironolactone treats fluid retention in those with cirrhosis of the liver, congestive heart failure, or nephrotic syndrome (a kidney disorder). Spironolactone is also used in treating or in prevention of hypokalemia (low levels of potassium in the blood).
Common side effects of spironolactone may include skin rash, headache, dizziness, mild nausea or vomiting, stomach pain, or gas. These are not serious side effects, though you may wish to seek medical advice if any of these common symptoms become persistent.
Recent medical studies reported by the media in August 2012 about galectin-3, a protein that has the ability to identify those who are at higher risk of heart failure, also mentioned spironolactone (and several other drugs believed to have the ability to counteract cardiac fibrosis) improving outcomes in heart failure patients. The galectin-3 study was scheduled to be published online by the Journal of the American College of Cardiology on 29 August 2012, and in the journal's print issue on 2 October 2012.