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. Delayed allergic reaction to plaquenil Chloroquine for treating malaria Cardiomyopathy is a progressive disease of the myocardium, or heart muscle. In most cases, the heart muscle weakens and is unable to pump blood to the rest of the body as well as it should. Chloroquine Hydroxychloroquine-induced cardiomyopathy is a rare but potentially life-threatening condition. Cessation of the culprit drug, along with aggressive afterload reduction therapy, has been associated with halting of disease progress and even improvement in patients' clinical and histologic status. Hydroxychloroquine Plaquenil is considered a disease-modifying anti-rheumatic drug DMARD. It can decrease the pain and swelling of arthritis. It may prevent joint damage and reduce the risk of long-term disability. Hydroxychloroquine is in a class of medications that was first used to prevent and treat malaria. 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 related cardiomyopathy Side Effects of Plaquenil Hydroxychloroquine, Warnings, Uses, Hydroxychloroquine-induced restrictive cardiomyopathy. Chloroquine vivaxHydroxychloroquine and fastingWeight gain with plaquenilPain relief from plaquenil Cardiomyopathy kahr-dee-o-my-OP-uh-thee is a disease of the heart muscle that makes it harder for your heart to pump blood to the rest of your body. Cardiomyopathy can lead to heart failure. The main types of cardiomyopathy include dilated, hypertrophic and restrictive cardiomyopathy. Cardiomyopathy - Symptoms and causes - Mayo Clinic. Hydroxychloroquine Plaquenil. Plaquenil - FDA prescribing information, side effects and uses. The differential diagnosis for left ventricular dysfunction in systemic lupus erythematosus patients is wide and includes coronary artery disease, myocarditis, and valvular disease. This case illustrates the importance of also considering hydroxychloroquine toxicity, as it can be reversed by cessation of the drug. Postmarketing cases of life-threatening and fatal cardiomyopathy have been reported with use of Plaquenil and chloroquine. Patients may present with atrioventricular AV block, pulmonary hypertension, sick sinus syndrome or with cardiac complications. ECG findings may include AV, right or left bundle branch block. Our patient likely had baseline mild proximal myopathy secondary to hydroxychloroquine with her acute decompensation due to a second myotoxic drug, colchicine. To our knowledge this is the first documented case of a myopathy induced by both hydroxychloroquine and colchicine supported by unique electron microscopy findings.