Myoclonus is not a known side effect of ranolazine. We report a case of myoclonus in a 72-year-old female who underwent cardiac catheterization for angina and was started on ranolazine after the procedure. Two days after ranolazine therapy on 1000？mg per day in divided doses, myoclonus developed, which severely impaired her normal activity. Her symptoms resolved 2 days after discontinuation of ranolazine. Ranolazine was resumed after discharge from hospital with recurrent myoclonus after two days of therapy. The causal relationship between ranolazine and myoclonus was suggested by cessation of myoclonus after ranolazine was discontinued. 1. Introduction Chronic angina is a debilitating condition affecting nearly 6 million Americans. Current standard therapy includes beta-blockers, calcium channel blockers, and long acting nitrates. Some patients may be intolerable to standard therapy due to their side effects [1]. Ranolazine is new agent introduced into clinical practice in 2006. It is an extended release antianginal drug and is intended to act without reducing heart rate or blood pressure. Ranolazine is specifically indicated for the treatment of chronic angina in patients that failed previous anti-ischemic therapy [2]. It is contraindicated in patients with QT prolongation [3]. It has a piperazine compound that belongs to a group known as partial fatty-acid oxidation inhibitors [4]. Initially, the main anti-anginal effects of ranolazine were thought to be related to the actions of ranolazine to shift adenosine triphosphate (ATP) production away from fatty-acid oxidation toward glycolysis [5, 6]. Recent evidence suggests that ranolazine is an inhibitor of the late sodium current which results in a reduction of the intracellular sodium and calcium overload in ischemic cardiac myocytes [7–9]. 2. Case Report This is a 72-year-old female who presented to the emergency department with history of chest pain and non-ST-segment elevation myocardial infarction (NSTEMI). Her past medical history was significant for intermittent chest pain. She underwent cardiac catheterization with placement of 2 drug eluding stents and was started on ranolazine for symptomatic relief of NSTEM with angina. Her medication list included atorvastatin 20？mg daily, clopidogrel 75？mg daily, aspirin 162？mg daily, diltiazam 60？mg four times a day, and ranolazine 500？mg twice daily. She presented 2 days after discharge with myoclonic jerks in her upper and lower extremities. She was readmitted in the hospital for evaluation of myoclonus. At the time of her hospitalization, ranolazine was
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