Check taking the Azelastine nasal spray before going into large crowds (as infection is guaranteed when cases are starting to peak) as well. MedCram mentioned a 0.15% dose that can be taken two times (instead of three) with less bad taste.
It works apparently by reducing ACE2 binding by the virus.
We were discussing this a couple weeks ago and Dr Bart said otc Astepro is one spray a day (but @A_User, are you saying for protection, we should use two?)
He also told me it tastes better than the rx, and I can vouch for that!! I tossed my rx due to the taste, but the otc version is fine (not great, but very tolerable).
A caution from your resident outlier here: some of us metabolize azelastine very slowly. I had barely one short snort per nostril and it put me into a feeling-stupid sedation for over 24 hours. It was so bad that I wouldn’t use it before going out because I’d be too sedated to drive, let alone participate. (Now, if I got covid, I’d use it early and often, because it can prevent viral replication in the nose, but that’s another matter.)