Abstract
The Food and Drug Administration has recently approved the off-label use of hydroxychloroquine (HCQ) for the treatment of coronavirus disease 2019 (COVID-19) infections. However, a recent study not only failed to demonstrate HCQ efficacy but also documented a serious side effect of COVID-19 therapy with HCQ: QT prolongation and secondary arrhythmia. HCQ has been used as an off-label drug and deemed safe and effective for the treatment of oral lesions, such as Sjogren syndrome (SS), chronic ulcerative stomatitis (CUS), and oral lichen planus (OLP). Because HCQ may be appropriately used for the off-label treatment of SS, CUS, and OLP, relevant safety concerns regarding HCQ therapy with regard to dosage, drug-to-drug interactions, and QT prolongation and secondary arrhythmia are discussed here. Because of the possibility of decreased pharmacy supplies of HCQ, replacement drugs with respect to patients with SS, CUS, and OLP being successfully treated with HCQ are also discussed.