The patient had been treated with hydroxychloroquine for two years prior to presentation. After thorough workup for secondary causes of QT interval prolongation hydroxychloroquine was discontinued and the patient’s QT interval shortened. What is the maximum dose of plaquenil Plaquenil how does it treat lupus Hydroxychloroquine diarea Drug-induced QT/QTc interval prolongation is a surrogate indicator for increased risk of drug-induced torsade de pointes TdP, a potentially lethal polymorphic ventricular tachycardia. Risk factors for drug-induced QT/QTc prolongation include female gender, Hydroxychloroquine sulfate tablets are indicated for the treatment of chronic discoid lupus erythematosus and systemic lupus erythematosus in adults. Rheumatoid Arthritis. Hydroxychloroquine sulfate tablets are indicated for the treatment of acute and chronic rheumatoid arthritis in adults. Of the documented medications known to cause QT interval prolongation hydroxychloroquine HCQ is extremely rare in the literature. HCQ is an antimalarial that has become the cornerstone for treatment of systemic lupus erythematosus SLE 9. The patient was noted to have mild prolongation of the QT interval on electrocardiogram prior to initiation of hydroxychloroquine therapy which was exacerbated by its use and may have been caused due to toxicity from underlying renal failure. The patient was treated with mexiletine to prevent sudden ventricular arrhythmias, which was unique compared to other documented cases in which lidocaine was used. Hydroxychloroquine qt prolongation CredibleMeds Home, DailyMed - HYDROXYCHLOROQUINE SULFATE tablet, film coated Sub for plaquenil Chronic hydroxychloroquine use associated with QT prolongation and refractory ventricular arrhythmia. Clin Toxicol Phila. 2006; 442173-5 ISSN 1556-3650 Chen CY; Wang FL; Lin CC. BACKGROUND Hydroxychloroquine HCQ is used for treatment of lupus erythematosus. The cardiac toxicity of HCQ has focused primarily on acute intoxication. Chronic hydroxychloroquine use associated with QT.. Life Threatening Severe QTc Prolongation in Patient with.. Hydroxychloroquine Tablets - FDA prescribing information.. It is recommended that hydroxychloroquine be discontinued if ocular toxicity is suspected and the patient should be closely observed given that retinal changes and visual disturbances may progress even after cessation of therapy. Cardiac Effects, including Cardiomyopathy and QT prolongation Postmarketing cases of Commonly used on holidays in malaria prone destinations, chloroquine and hydroxychloroquine will not be over familiar to the emergency physician. However, it is one of the leading causes of drug overdose in malaria prone countries and also the occasional toddler has managed to consume the grandparents lupus or rheumatoid arthritis medication leading to lethal consequences. HS34-HS40. ABSTRACT QT prolongation is a rare adverse event associated with many drugs, including antipsychotics and antidepressants. The majority of cases have occurred in patients taking an offending agent with multiple identifiable risk factors for corrected QT QTc prolongation.