What are the critical differences between bipolar disorder and schizophrenia?

I don't know anymore: This is a good question. Most of my patients who i thought had schizophrenia (psychotic symptoms without major mood symptoms) later developed mood symptoms needing mood medications. Many bipolar patients develop psychotic symptoms (paranoia, hallucinations) and respond often to just antipsychotic meds. With early good treatment both conditions can have a good prognosis. Don't delay treatment.

Mood: Bipolar disorder is a mood disorder which includes distinct episodes of highs (mania) and lows (depression). Schizophrenia is a chronic thought disorder which includes hallucinations and delusions. Schizoaffective disorder is schizophrenia with depression, mania, or both.

Thoughts vs Moods: Schizophrenia is a disorder of a person's thoughts, known as psychosis. Psychosis involves having hallucinations and/or delusions. In schizophtenia, the most common hallucinations are auditory, whereby the person hears voices and the most common delusions are paranoid in nature. Bipolar disorder involves a problem with one's mood. Manic episodes, or extreme mood elevations is the main hallmark.