In the case reported by Kuipers et al. [17], the subject received chloroquine and had a G6PD deficiency; hydroxychloroquine was administered to the subject reported by Faisal et al. [20] (the G6PD status was not reported); and in the three cases reported by Naymagon et al. [18] all received hydroxychloroquine, while one subject was tested for G6PD deficiency and was positive.