Brief psychotic disorder vs schizophrenia are probably the most confusing of all of the other types of psychotic disorders. This condition is also called mania, delirium and schizophrenia. These are not all accurate descriptors. The fact is, there are many variations of this, ranging from a few months to several years of this, with several different types.
A brief psychotic disorder occurs in between schizophrenia and mania, often starting after an acute episode of schizophrenia. Usually, it is seen in young people but can happen to adults as well.
There are two different types of milder forms of brief psychotic disorder - manic-depressive psychosis and schizophrenia without psychotic symptoms. The milder form does not develop into severe conditions as clearly defined by the DSM.
Unfortunately, this disorder is so well known, there is a tendency to generalize the symptoms to other similar disorders and misdiagnose as being mentally ill, when in fact it is just an adjustment disorder. While the symptoms and behavior may be similar to that of other disorders, such as depression or bipolar disorder, the disorder is not as clear cut.
One sign of the disorder is mood swings, such as irritability or depression. However, there is no clear difference between manic and depressive disorders, with both ending with a manic episode followed by a depressed episode.
Psychotic symptoms include auditory and visual hallucinations, delusions, confusion, paranoia, bizarre behavior, auditory and visual disorientation, delusions of grandeur, odd behaviors and disturbances of thought processes. Other more common symptoms include an inability to process information, inappropriate behavior, insomnia, sweating, muscle tension, shaking, insomnia, nausea, abdominal pain, palpitations, a sense of unreality and feelings of paranoia.
Cognitive problems may also be present, causing hearing loss and depression. They usually occur in the elderly, in people who are very intelligent, or people with limited intellectual abilities.
The symptoms of a brief psychotic disorder may be similar to other types of psychosis, but the main distinction is the level of cognitive impairment. Usually, someone with a milder form of the disorder will recover completely by themselves, with no treatment.
However, when people are diagnosed with schizophrenia, their behavior will be very limited and will not progress past normal levels. They will normally need treatment. Other conditions such as ADHD, bipolar disorder, depression and OCD can all result in similar short-term episodes.
In the world of the medical profession, this is considered rare, and many doctors still believe that it is caused by genetics and is not something that can occur to anyone on a regular basis. The truth is, for some people, it can.
Given the limitations of the data, I will assume that a brief psychotic disorder is slightly different than a schizophrenia-without-psychotic symptoms. However, as long as someone's symptoms are consistent with the kind of mania or depression that is considered to be a "classic" form of schizophrenia, then there is a milder form of this disorder.