Bipolar disorder and schizophrenia - many people confuse these two mental illnesses. Likely, this is due to misinformation about both disorders. Bipolar and schizophrenia, though, are two completely different psychiatric disorders and are even in two different classes of mental illness.
Mood Disorders vs. Psychotic Disorders
Bipolar disorder is what’s known as a mood disorder, or an affective disorder. The primary symptom in mood disorders, as the name suggests, is a disturbance in mood. In bipolar disorder, the symptoms surround mood swings wherein a bipolar episode can be either of a very low mood (depression) or a very high mood (mania). While schizophrenia can affect mood, mood disturbance is not its primary symptom.1
Schizophrenia is known as a psychotic disorder. The primary symptom in psychotic disorders is psychosis or the inability to tell reality from fantasy. Delusions (false beliefs) and hallucinations (perceiving things that aren’t there) are common in schizophrenia. While psychosis may be part of a manic or depressed episode in bipolar disorder, those are not the primary symptoms.2 (more on schizophrenia and psychosis)
Bipolar and Schizophrenia – Similarities
Bipolar disorder and schizophrenia are both episodic in nature, meaning that some of the time a person is symptom-free while other times they are in a symptomatic episode. Schizophrenia and bipolar disorder also both impact everyday functioning, relationships, work and home life; however, they may do so in different ways.
Other ways in which bipolar and schizophrenia are similar includes:
- Symptoms starting between age 16-30
- Can both experience the symptoms of psychosis
- Can both experience the symptoms of depression
- May be treated with the same medication (antipsychotics)
- Can be successfully treated
- Associated with drug and alcohol abuse
- Neither are a "split personality"
More on schizophrenia symptoms and diagnosis criteria here.
Bipolar vs. Schizophrenia – What’s Different?
The primary difference between bipolar disorder and schizophrenia is the prevalence and severity of different symptoms. These symptoms are the way in which each disorder is separately diagnosed. For example, bipolar disorder is diagnosed primarily by the presence of periods of both mania and depression, whereas schizophrenia is diagnosed largely based on symptoms of psychosis.
Other ways in which schizophrenia and bipolar disorder differ include:3,4
- People with schizophrenia may appear to have a “flattened” mood (not happy or sad), whereas people with bipolar often appear moody
- People with bipolar disorder may have psychotic symptoms that are related to mood – such as being Jesus when happy – whereas people with schizophrenia tend to have psychotic symptoms that aren’t related to mood
- People with schizophrenia may have trouble understanding information and using it to make decisions (executive functioning)
- People with schizophrenia may stop talking in the middle of a sentence and feel the words were just "taken out of their head"
- People with schizophrenia have a greater tendency to be suspicious and paranoid