Ranolazine (Ranexa) is the first drug in more than a decade to receive FDA approval for treatment of chronic angina. How Ranexa works isn't fully understood, but it's known to prolong the QT interval. It's appropriate only for patients who haven't responded to other antianginal drugs (including long-acting nitrates, calcium channel blockers, and beta-blockers). In clinical trials, Ranexa was less effective in women than in men. Typical adverse reactions included dizziness, headache, constipation, and nausea.