Major depression is a distressing mental health problem, but it is a fairly common and treatable one. Depression combined with a psychosis like paranoia is more unusual. Psychosis refers to a loss of touch with reality. One study found that major depression with psychotic features affected only four out of 1000 people in the general public. About 15 percent of people who have been diagnosed with major depression report one or more psychotic symptoms. The combination of depression and paranoia may also be caused by other diagnoses including schizophrenia, schizoaffective disorder, bipolar disorder and Alzheimer's disease.
Paranoia is one type or subset of psychosis. Most people have occasional, fleeting paranoid thoughts, but true paranoia is a fixed, irrational belief that others are out to do harm to the person with paranoia. The person also often has an inflated sense of his or her own importance. For instance, the person with depression and paranoia might believe that he or she possesses knowledge of impending doom and that the police and the FBI are out to silence him or her.
The person with paranoia is understandably suspicious, often interpreting innocent behavior, like a police car driving by the house, as evidence of a sinister plot. The paranoid person may express anger or even hatred toward those he or she sees as persecutors. Although most people with mental illness are not violent, the paranoid person may lash out at others, believing he or she is acting in self defense. A paranoid person may also turn on loved ones, thinking that they are betrayers. Another characteristic of paranoia is rigidity. The person may engage in strict rituals that give him or her a sense of safety and security. The person who is experiencing depression and paranoia may appear agitated and fearful. He or she may have a hard time relaxing, not even letting his or her guard down to eat or sleep.
The risk of suicide is higher for those experiencing depression with psychotic features than it is for depressed people without psychosis. Depression with paranoia is also more likely to resist the usual forms of treatment. The most effective therapy appears to be a combination of antidepressant and antipsychotic medications. In extreme cases, when the symptoms do not respond to treatment or when the person poses an imminent danger to self or others, psychiatrists may recommend a course of electroconvulsive therapy, also known as ECT or shock treatment. Administered humanely while the person is under anesthetic, ECT usually brings about fast, satisfactory results.