Table 2.

Some of COVID-19 Known Unknowns

Factors	Available information
NSAIDS eg Ibuprofen	► There is little evidence to suggest that NSAIDS such as Ibuprofen upregulates ACE2 receptors.48,49 However, the existing literature does not currently provide conclusive evidence for or against the use of NSAIDs in the treatment of COVID-19 patients. ►Caution should be exercised until further evidence, specific to this infection strain, emerges.
ACE-I or ARBs	► Data suggested that ACE2 expression upregulated in those treated with ACE-I or ARBs.48 With no conclusive pieces of evidence, it has been suggested for COVID-19 patients to remain on these antihypertensive medications.50
Susceptibility to COVID-19	► A study of single-cell transcription51 suggested that the Asian populations are more likely affected than Caucasian and African American due to higher ACE-2 receptors density. But no further evidence has supported this investigation.

Abbreviations: NSAIDS, non-steroidal anti-inflammatory drugs; ACE, angiotensin-converting enzyme; ARBs, angiotensin receptor blockers.