Have fluid behind ears/ pressure/jaw pain. dr. said no infection and prescribed flonase. will this cause a brain abscess, osteomyelitis or sepsis?

No infection: suspected. Need infection to get Osteomyelitis (spread of infection to bone) sepsis (infection that has spread to the blood stream) or a brain abscess.

None of the above: If your doc told you there was no infection then, whatever the fluid is behind your ears is STERILE...meaning that no bacteria are inside. If there are no bacteria in this fluid then, its's pretty much a foregone conclusion that this fluid CANNOT CAUSE or be the cause, either directly, or indirectly of an abscess anywhere, osteomyelutusm or sepsis. Cheers!

All of the things: you mention are infections. If you have negative pressure or uninfected fluid in your middle ears spaces, there is no infection that could spread. The Flonase is to reduce swelling & edema of mucous membranes of your upper respiratory tract, thus allowing your Eustachian tubes to become patent, or open, again at their junction with your nasopharynx & middle ear pressure to normalize.

No: no infection just nasal congestion blocking the eustacain tube and the Flonase will reduce the swelling and resolve the symptoms.

I hope not: Do you think your physician would suggest something that would cause all of those severe and dramatic problems? If you do, you need to find another doctor.