Can flonase usage cause seizures to occur if you have a seizure disorder?

Not expected: This is not a side effect from nasal steroid.

Not likely: Flonase is steroid nasal spray. It should not cause seizures.

Very unlikely: Since delivered locally into nasal passages, should not affect brain function directly or indirectly. In other words, should be not cause seizures. But do not get distracted and miss your anti-epileptic drugs, as these are indeed crucial.