Heart failure results from reduced cardiac output and elevated sympathetic discharge, leading to vasoconstriction and sodium and water retention. Drugs used to treat heart failure include diuretics, ACE inhibitors, beta blockers, aldosterone receptor antagonists, and vasodilators. Diuretics are first-line to reduce preload and relieve edema. ACE inhibitors and ARBs reduce afterload while beta blockers attenuate sympathetic activation. Aldosterone receptor antagonists prevent remodeling and reduce mortality.