What can cause a sudden change in personality?

What can cause a sudden change in personality? Personality changes can be caused by a mental illness like depression, bipolar disorder, or personality disorders. It may also be caused by physical illnesses like a urinary tract infection (especially in older adults), concussion, or brain tumor.

Personality changes can be caused by a mental illness like depression, bipolar disorder, or personality disorders. It may also be caused by physical illnesses like a urinary tract infection (especially in older adults), concussion, or brain tumor.