Could Someone Please Explain the Phrase “Psychosis Is a Symptom”?

Question by Skepticat: Could someone please explain the phrase “psychosis is a symptom”?
I’ve just seen it in people’s answers twice, but I thought psychosis was a category of mental illnesses, including schizophrenia, and some others which are less common.

If I’ve been understanding, and using, the word incorrectly, I’d like to know. Also, if psychosis IS a symptom, would someone please explain its characteristics?

Best answer:

Answer by Sheepicorn
Here http://en.wikipedia.org/wiki/Psychosis
“People experiencing psychosis may report hallucinations or delusional beliefs, and may exhibit personality changes and disorganized thinking. This may be accompanied by unusual or bizarre behavior, as well as difficulty with social interaction and impairment in carrying out the activities of daily living.

A wide variety of central nervous system diseases, from both external toxins, and from internal physiologic illness, can produce symptoms of psychosis. This disease link has led to the metaphor of psychosis as the ‘fever’ of CNS illness—a serious but nonspecific indicator.”

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