The short answer to this question is, “Yes.” Depression can cause psychotic symptoms, including delusions and hallucinations. These symptoms will most often reflect depressive themes like personal inadequacy, guilt, disease, death, punishment, and worthlessness. For example, a person who is experiencing depression with psychosis may develop false beliefs that he or she is afflicted with a physical illness or hear ridiculing, criticizing voices. In addition to these types of symptoms, people experiencing depression with psychosis might experience other symptoms typical of depression such as agitation, anxiety, hypochondria, insomnia or excessive sleep, poor concentration and lack of energy or motivation.
Psychosis is more common in severe depression, affecting roughly one in four people who are admitted to the hospital for depression. Those who have experienced one episode of psychosis with depression can be at an increased risk of recurrent depressive episodes, bipolar disorder, and suicide. For these reasons, accurate diagnosis is important.
Effective treatment for depression with psychosis involves intensive psychiatric treatment and therapy in a monitored setting. A combination of antidepressant and antipsychotic medication is often used early on in the stabilization of symptoms. Unlike some other disorders that include symptoms of psychosis, like schizophrenia, a person may not need to take an antipsychotic medication long-term to successfully treat the illness. Electroconvulsive therapy (ECT) can be effective in treating this illness but it is usually prescribed only after other means of treatment have proven ineffective.
The good news regarding depression with psychosis is that treatment is commonly very effective. People are frequently able to recover from an acute phase of this illness within a few weeks or months. Continued psychiatric follow-up is necessary, however, and it is common that individuals experiencing this illness will need to work closely with their doctors to find the most effective treatment for their depression with the fewest side effects.