A pre-print paper (medrxiv) suggests that while, 'short-term hydroxychloroquine treatment is safe, addition of azithromycin may induce heart failure and cardiovascular mortality, potentially due to synergistic effects on QT length' and therefore, needs more caution.

Title of Article: Safety of hydroxychloroquine, alone and in combination with azithromycin, in light of rapid wide-spread use for COVID-19: a multinational, network cohort and self-controlled case series study

doi: https://doi.org/10.1101/2020.04.08.20054551

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