Hydroxychloroquine had generated a lot of promise initially in coronavirus disease 2019 pandemic following its reported in-vitro efficacy. Based on in-vitro studies and emerging clinical data its prophylactic use in healthcare workers was recommended by various healthcare bodies such as Indian Council of Medical Research. We undertook a study to check if hydroxychloroquine accorded any prophylactic advantage in healthcare workers in a departmental study under publication. The results revealed that hydroxychloroquine failed to provide any prophylactic protection. Serum levels of hydroxychloroquine were measured to cross-validate compliance of prophylactic doses. We went ahead to check correlation between time since the last dose of hydroxychloroquine and its serum levels. A poor correlation between the two was noted (r=0.08; p=0.58) which reinforces the underlying variability and unpredictability of pharmacokinetics of hydroxychloroquine.