Hydroxychloroquine: Adverse Drug Reaction Profile of an Old Drug in a New Situation

Background: Hydroxychloroquine (HCQ) has been extensively used during the COVID-19 pandemic both as a therapeutic and prophylactic drug. HCQ is generally well tolerated; however, adverse drug reactions (ADRs) in COVID-19 need further exploration. In this study, we have determined the type and pattern of ADRs of HCQ as a prophylactic and therapeutic drug in COVID-19. Methods: All spontaneous suspected ADR reports due to HCQ in COVID-19 patients submitted to the ADR monitoring of a tertiary care hospital were included. Additionally, a survey was designed for active surveillance of ADRs among healthcare professionals (HCPs) who were on prophylaxis with HCQ. The ADRs were analyzed to determine severity, causality, and preventability using the Hartwig Scale, World Health Organisation-Uppasala Monitoring Centre (WHO–UMC) scale, and modified Schumock and Thornton criterion respectively. Results: Sixty-four ADR reports were received from COVID-19 patients. A total of 78 ADRs were reported by 49 HCPs who were on HCQ prophylaxis. The majority of the patients had ADRs related to skin and soft tissues (37.5%), whereas the HCPs on prophylaxis mostly had gastrointestinal complaints (42.3%). ADRs observed in HCPs on prophylaxis were mild, not requiring any intervention. However, 50% of ADRs in patients were of “moderate” category. Conclusion: Undiscerning and unsupervised use of HCQ can expose the general population as well as patients to serious adverse drug effects. Utmost care is necessary before using HCQ prophylactically or for treatment in COVID-19.