Mix 1/4 c each in a small jar:
Neem powder - it's antibacterial, antiviral and antiinflammatory
Guducchi -supports immune system
Tulsi powder - supports respiratory system

Then take 1/2 tsp mixed with warm water 3x /day for two to three days. Can also take this before going to a party... If you're not drinking alcohol...

Additionally, you can do a saline nasal rinse -- I wrote an article about covid and the nasal passages 
https://yogawithlois.com/nasal-irrigation-neti-pot-clears-sinuses-and-steadies-the-mind/