I do not see any problem and would do this
since herbs are as foods. The main caveat however
would be that if you are not in a relative good
place with your health, that the olive leaf could
precipitate a cleansing detox which you would not
want to do. If you are used to taking this though,
it would help your immune system.

Also using a nasal irrigator or a neti pot would
be other options which you may consider.

Good luck with your surgery~~and healing~~

best wishes & blessings,
Zoe

-_-