Results from a double-blind trial suggest that off-label use of the oral antihyperglycemic drug metformin in patients with COVID-19 may decrease the risk of post-acute sequelae of SARS-CoV-2 infection ("long COVID").

On April 29, the NIH recommended against use of the antiparasitic drug ivermectin for treatment of COVID-19 outside of a clinical trial. The recommendation was made because recent randomized, placebo-controlled trials of ivermectin have produced negative results and because alternative drugs that have been shown to be effective for treatment of COVID-19 are available.

Rosacea is a common, chronic inflammatory facial eruption of unknown cause. It is more prevalent in women than in men, and disease onset typically occurs after age 30. Rosacea is characterized by erythema, telangiectasia, and flushing, and sometimes by recurrent, progressive crops of acneiform papules and pustules, usually on the central part of the face. Some patients develop granulomas and tissue hypertrophy, which may lead to rhinophyma (a bulbous nose), particularly in men. Blepharitis and conjunctivitis are common. Keratitis and corneal scarring occur rarely.