Burn out is when a human caster pushes themselves past their limits. It can be temporary or permanent

Effect

While there is no illness to be past,social pressures are a big cause, along with the casters own haste and frustration

Being a caster

It is more common for casters, young ones at that, in academia

Pushing past the casters limits and experience. Not taking breaks. while no caster is immune, It is more common for casters, young ones at that, in academia

In fatal cases, 100%
Temp and permanent usually survive but may still die depending on factors such as what they where trying to do, experience, how hard the after effect hit them and what care they receive.

temporary, permanent, and fatal

temp burnout usually resolves itself anywhere from a few hours to a few months depending on how experienced the caster was and what they where trying to do. The longest on record was three years

Casters will feel as if they are burning from the inside out around the chest. In the case of a fatal burn out, this sensation will gulf them and their system will shut down. Then the caster will feel as if a cold hard weight rested on their chest. In permanent cases, the caster will feel a shattered sensation during this stage. Headache or migraine, anxiety, depression, tachycardia, fever that usually resolves anywhere from an hour to a few weeks after

anxiety, depression, delirium, a looming sense of doom
suicidal dealation, while not common, has been documented

usually resolves anywhere from an hour to a few weeks after

sweating
possibility of bursting blood vessels resulting in nose bleed or blood shot eyes
glazed eye

supportive care