Could long term high levels of cortisol make a person suicidal from being in constant fight to flight mode?

Stress is dangerous: Long term high levels of stress often can lead to depression, and should not be taken lightly. Work with your doctor and psychologist for a combination of medications and strategies to reduce your stress levels, and be sure to seek immediate help if you are feeling suicidal.

Definitely: High cortisol levels, particularly if you're taking cortisone medication at high levels for a long period of time, can lead to psychiatric consequences. So can suddenly stopping long term replacement without careful tapering of the dose.