“ The use of hydroxychloroquine in patients with a history of cardiovascular disease requires careful consideration due to potential cardiac side effects. hcqplaquenil.com plaquenil for lupus Hydroxychloroquine has been associated with cardiotoxicity, including QT interval prolongation and arrhythmias, particularly in patients with underlying cardiac risk factors or concomitant use of other QT-prolonging medications. Healthcare providers should assess cardiovascular risk factors and monitor cardiac function regularly in patients receiving hydroxychloroquine therapy. ”