People are using zinc lozenges to ‘treat’ (or prevent) COVID-19. There is no evidence of its value in COVID-19. An opinion piece from China suggests a variety of vitamins etc. However, it is backed only by lab science
A systematic review of zinc’s value in colds suggests it could shorten symptoms but the evidence base is poor.
A Cochrane Review Protocol of “Zinc for preventing and treating the common cold” suggests there may be merit but was never completed.