Diagnosis
Differential diagnosis
Psychotic symptoms are often missed in psychotic depression, either because patients do not think their symptoms are abnormal or they attempt to conceal their symptoms from others. On the other hand, psychotic depression may be confused with schizoaffective disorder. Due to overlapping symptoms, differential diagnosis includes also dissociative disorders. Treatment
Several treatment guidelines recommend pharmaceutical treatments that include either the combination of a second-generation antidepressant and atypical antipsychotic or tricyclic antidepressant monotherapy or electroconvulsive therapy (ECT) as the first-line treatment for unipolar psychotic depression.There is no evidence for or against the use of mifepristone. Combined antidepressant and antipsychotic medications
There is some evidence indicating that combination therapy with an antidepressant plus an antipsychotic is more effective in treating psychotic depression than either antidepressant treatment alone or placebo. In the context of psychotic depression, the following are the most well-studied antidepressant/antipsychotic combinations:
First-generation

Amitriptyline/perphenazine
Amitriptyline/haloperidolSecond-generation

Venlafaxine/quetiapine
Olanzapine/fluoxetine
Olanzapine/sertraline

Antidepressant medications
There is insufficient evidence to determine if treatment with an antidepressant alone is effective. Tricyclic antidepressants may be particularly dangerous, because overdosing has the potential to cause fatal cardiac arrhythmias. Antipsychotic medications
There is insufficient evidence to determine if treatment with antipsychotic medications alone is effective. Olanzapine may be an effective monotherapy in psychotic depression, although there is evidence that it is ineffective for depressive symptoms as a monotherapy; and olanzapine/fluoxetine is more effective. Quetiapine monotherapy may be particularly helpful in psychotic depression since it has both antidepressant and antipsychotic effects and a reasonable tolerability profile compared to other atypical antipsychotics.
Psychotic depression, also known as depressive psychosis, is a major depressive episode that is accompanied by psychotic symptoms. It can occur in the context of bipolar disorder or major depressive disorder. It can be difficult to distinguish from schizoaffective disorder, a diagnosis that requires the presence of psychotic symptoms for at least two weeks without any mood symptoms present. Unipolar psychotic depression requires that the psychotic features occur only during episodes of major depression. Diagnosis using the DSM-5 involves meeting the criteria for a major depressive episode, along with the criteria for "mood-congruent or mood-incongruent psychotic features" specifier. Signs and symptoms
Individuals with psychotic depression experience the symptoms of a major depressive episode, along with one or more psychotic symptoms, including delusions and/or hallucinations. Delusions can be classified as mood congruent or incongruent, depending on whether or not the nature of the delusions is in keeping with the individuals mood state. Common themes of mood congruent delusions include guilt, persecution, punishment, personal inadequacy, or disease. Half of patients experience more than one kind of delusion. Delusions occur without hallucinations in about one-half to two-thirds of patients with psychotic depression. Hallucinations can be auditory, visual, olfactory (smell), or haptic (touch), and are congruent with delusional material. Affect is sad, not flat. Severe anhedonia, loss of interest, and psychomotor retardation are typically present. Cause
Psychotic symptoms tend to develop after an individual has already had several episodes of depression without psychosis. However, once psychotic symptoms have emerged, they tend to reappear with each future depressive episode.