Although not all of these side effects may occur, if they do occur they may need medical attention. Check with your doctor immediately if any of the following side effects occur while taking hydroxychloroquine: Incidence not known Some side effects of hydroxychloroquine may occur that usually do not need medical attention. Tapering off plaquenil Plaquenil fda Can plaquenil cause vasculitis Coronary heart disease is found among people who take Plaquenil, especially for people who are female, 60+ old, have been taking the drug for 1 - 6 months, also take medication Vioxx, and have Osteoporosis Chloroquine CQ and hydroxychloroquine Plaquenil HCQ have been used for many years, initially for the treatment of malaria but now more commonly for the treatment of inflammatory diseases such as rheumatoid arthritis and lupus 1. It is now considered for new disease applications in diabetes, heart disease and adjunct cancer therapies 2. Note This document contains side effect information about hydroxychloroquine. Some of the dosage forms listed on this page may not apply to the brand name Plaquenil. For the Consumer. Applies to hydroxychloroquine oral tablet. Along with its needed effects, hydroxychloroquine the active ingredient contained in Plaquenil may cause some unwanted effects. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. These side effects may go away during treatment as your body adjusts to the medicine. Plaquenil cardiac Plaquenil hydroxychloroquine – New Warnings, Hydroxychloroquine Plaquenil Toxicity and. Prednisone and plaquenil during pregnancyShow me a picture of hydroxychloroquine Use hydroxychloroquine with caution in patients with cardiac disease or other conditions that may increase the risk of QT prolongation including cardiac arrhythmias, congenital long QT syndrome, heart failure, bradycardia, myocardial infarction, hypertension, coronary artery disease, hypomagnesemia, hypokalemia, hypocalcemia, or in patients. Plaquenil hydroxychloroquine sulfate dose, indications.. Plaquenil Side Effects Common, Severe, Long Term -. Hydroxychloroquine - Wikipedia. PLAQUENIL prolongs the QT interval and should not be administered with other drugs that have the potential to induce cardiac arrhythmias. Also, there may be an increased risk of inducing ventricular arrhythmias if PLAQUENIL is used concomitantly with other arrhythmogenic drugs. Cardiac disorders Cardiomyopathy which may result in cardiac failure and in some cases a fatal outcome see WARNINGS and OVERDOSAGE. PLAQUENIL prolongs the QT interval. Ventricular arrhythmias and torsade de pointes have been reported in patients taking PLAQUENIL see OVERDOSAGE and DRUG INTERACTIONS. Hydroxychloroquine Plaquenil is used to treat malaria, lupus, and rheumatoid arthritis. Learn about side effects, warnings, dosage, and more.