Every one of us always has a doctor’s note in our possession . Each time you get your medical your AME (a medical doctor) signed his name on that document. The FAR’s referenced on that document state that you cannot fly in a medically deficient state. Federal law associated with the possession of a FAA medical permits you on an individual basis to determine your fitness for flight.
If your company ever asks you for a doctor’s note just send them a copy of your medical signed by your AME and remind them that they already have your “doctor’s note” on file.