Psychosis as a symptom of a psychiatric<unk>  is first and foremost a diagnosis of exclusion. So a new-onset episode of psychosis cannot be considered to be a symptom of a psychiatric<unk>  until other relevant and known medical causes of psychosis are excluded, or ruled out. Many clinicians improperly perform, or entirely miss this step, introducing avoidable diagnostic error and misdiagnosis. An initial assessment includes a comprehensive history and physical examination. Although no biological laboratory tests exist which confirm<unk> , biological tests should be performed to exclude psychosis associated with or caused by substance use, medications, toxins or poisons, surgical complications, or other medical illnesses. Since non-medical mental health practitioners are not trained to exclude medical causes of psychosis, people experiencing psychosis should be referred to an emergency department or hospital. Delirium should be ruled out, which can be distinguished by visual hallucinations, acute onset and fluctuating level of consciousness, indicating other underlying factors which includes medical illnesses. Excluding medical illnesses associated with psychosis is performed by using blood tests to measure: * Thyroid-stimulating hormone to exclude hypo- or hyperthyroidism, * Basic electrolytes and serum calcium to rule out a metabolic disturbance, * Full blood count including ESR to rule out a systemic infection or chronic disease, and * Serology to exclude syphilis or HIV infection. Other investigations which may be performed include: * EEG to exclude epilepsy, and an * MRI or CT scan of the head to exclude brain lesions. Blood tests are not usually repeated for relapse in people with an established diagnosis of<unk> , unless there is a specific medical indication. These may include serum BSL if olanzapine has previously been prescribed, thyroid function if lithium has previously been taken to rule out hypothyroidism, liver function tests if chlorpromazine has been prescribed, CPK levels to exclude neuroleptic malignant syndrome, and a urinalysis and serum toxicology screening if substance use is suspected. Assessment and treatment may be done on an outpatient basis; admission to an inpatient facility is considered if there is a risk to self or others. Because psychosis may be precipitated or exacerbated by common classes of psychiatric medications, such as antidepressants, ADHD stimulant medications, and sleep medications, prescribed medication-induced psychosis should be ruled out, particularly for first-episode psychosis. This is an essential step to reduce diagnostic error and to evaluate potential medication sources of further patient harm. Regarding prescribed medication sources of patient harm, Yale School of Medicine Professor of Psychiatry Malcolm B. Bowers, Jr, MD wrote: Illicit drugs aren't the only ones that precipitate psychosis or mania—prescribed drugs can too, and in particular, some psychiatric drugs. We investigated this and found that about 1 in 12 psychotic or manic patients in an inpatient psychiatric facility are there due to antidepressant-induced psychosis or mania. That's unfortunate for the field of psychiatry and disastrous for some of our patients. Substance-induced psychosis should also be ruled out. Both substance- and medication-induced psychosis can be excluded to a high level of certainty while the person is psychotic, typically in an emergency department, using both a * Broad spectrum urine toxicology screening, and a * Full serum toxicology screening (of the blood). Some dietary supplements may also induce psychosis or mania, but cannot be ruled out with laboratory tests. So a psychotic person's family, partner, or friends should be asked whether he or she is currently taking any dietary supplements. Common mistakes made when diagnosing psychotic patients include: * Not properly excluding delirium, * Missing a toxic psychosis by not screening for substances and medications, * Not appreciating medical abnormalities (e.g., vital signs), * Not obtaining a medical history and family history, * Indiscriminate screening without an organizing framework, * Not asking family or others about dietary supplements, * Premature diagnostic closure, and * Not revisiting or questioning the initial diagnostic impression of primary psychiatric<unk> .<unk>  can only be diagnosed among those who have undergone a clinical evaluation with a psychiatrist. The criterion includes mental and physical symptoms such as, hallucinations or delusions, and depressive episodes. There are also links to bad hygiene and a troubled social life for those who suffer from<unk> . Research has failed to conclusively demonstrate a positive relationship between<unk>  and substance abuse. There are several theorized causations for the onset of<unk> , including, genetics, general brain function, like chemistry, and structure, and stress. Only after these relevant and known causes of psychosis have been ruled out can a psychiatric differential diagnosis be made. A mental health clinician will incorporate family history, observation of a psychotic person's behavior while the person is experiencing active symptoms, to begin a psychiatric differential diagnosis. Diagnosis also includes self-reported experiences, as well as behavioral abnormalities reported by family members, friends, or significant others. Mistakes in this stage include: * Not screening for dissociative<unk> s. Dissociative identity<unk>  and psychotic symptoms in<unk>  have considerable overlap, yet a different overall treatment approach. DSM-5 criteria The most widely used criteria for diagnosing<unk>  are from the American Psychiatric Association's Diagnostic and Statistical Manual of Mental<unk> s-5. The DSM-IV<unk>  definition was plagued by problems of being inconsistently (or unreliably) used on patients; when the diagnosis is made, it does not stay with most patients over time, and it has questionable diagnostic validity (that is, it does not describe a distinct<unk> , nor predict any particular outcome). These problems have been slightly reduced (or "modestly improved") in the DSM-5 according to Carpenter. When psychotic symptoms are confined to an episode of mania or depression (with or without mixed features), the diagnosis is that of a “psychotic” mood<unk> , namely either psychotic bipolar<unk>  or psychotic major depression. Only when psychotic states persist in a sustained fashion for two weeks or longer without concurrent affective symptoms is the diagnosis<unk> , schizophreniform<unk>  or schizophrenia. The second cardinal guideline in the DSM-5 diagnosis of<unk>  is one of timeframe. ::DSM-5 requires two episodes of psychosis (whereas DSM-IV needed only one) to qualify for the<unk>  diagnosis. As such, it is no longer an "episode diagnosis." The new<unk>  framework looks at the time from "the first episode of psychosis up to the current episode of psychosis, rather than only defining a single episode with co-occurring psychotic and mood syndromes." Specifically, one of the episodes of psychosis must last a minimum of two weeks without mood<unk>  symptoms, but the person may be mildly to moderately depressed while psychotic. The other period of psychosis "requires the overlap of mood<unk>  symptoms with psychotic symptoms to be conspicuous" and last for a greater portion of the<unk> . These two changes are intended by the DSM-5 workgroup to accomplish two goals: * Increase the diagnosis' consistency (or reliability) when it is used; * Significantly decrease the overall use of the<unk>  diagnosis. If the<unk>  diagnosis is used less often, other diagnoses (like psychotic mood<unk> s and schizophrenia) are likely to be used more often; but this is hypothetical until real-world data arrive. Validity problems with the diagnosis remain and await further work in the fields of psychiatric genetics, neuroimaging, and cognitive science that includes the overlapping fields of cognitive, affective, and social neuroscience, which may change the way<unk>  is conceptualized and defined in future versions of the DSM and ICD. Types One of two types of<unk>  may be noted in a diagnosis based on the mood component of the<unk> : * Bipolar type, when the disturbance includes manic episodes, hypomania, or mixed episodes—major depressive episodes also typically occur; * Depressive type, when the disturbance includes major depressive episodes exclusively—that is, without manic, hypomanic, or mixed episodes. Problems with DSM-IV<unk>  The American Psychiatric Association's DSM-IV criteria for<unk>  persisted for 19 years (1994–2013). Clinicians adequately trained in diagnosis used the<unk>  diagnosis too often, largely because the criteria were poorly defined, ambiguous, and hard to use (or poorly operationalized). Poorly trained clinicians used the diagnosis without making necessary exclusions of common causes of psychosis, including some prescribed psychiatric medications. Specialty books written by experts on<unk>  have existed for over eight years before DSM-5 describing the overuse of the diagnosis. Carpenter and the DSM-5<unk> s workgroup analyzed data made available to them in 2009, and reported in May 2013 that: a recent review of psychotic<unk> s from large private insurance and Medicare databases in the U.S. found that the diagnosis of DSM-IV<unk>  was used for about a third of cases with non-affective psychotic<unk> s. Hence, this unreliable and poorly defined diagnosis is clearly overused. As stated above, the DSM-IV<unk>  diagnosis is very inconsistently used or unreliable. A diagnosis is unreliable when several different mental health professionals observing the same individual make different diagnoses excessively. Even when a structured DSM-IV diagnostic interview and best estimate procedures were made by experts in the field that included information from family informants and prior clinical records, reliability was still poor for
Schizoaffective disorder
Schizophrenia
Bipolar disorder not otherwise specified
Schizophreniform disorder
Bipolar I disorder
Psychotic depression
Post-schizophrenic depression
Brief psychotic disorder