Depends on your clearance level
In my experience, just taking off the shelf painkillers without *WRITTEN* permission from your CO can get you in serious trouble
even if you have a valid reason for taking them.
I have heard of cases where TS clearance has been revoked because someone failed to disclose a visit out of state, to a
consultant and a 2 week course of strong opiates for a minor back problem which never returned.
It only came up because someone went digging and found the original script for said opiates.
I think they did eventually get the clearance back though but it took years.