Other conditions can cause similar symptoms as schizophrenia—especially the positive symptoms such as hallucinations. However, having similar symptoms does not mean you have schizophrenia. When similar symptoms are caused by other conditions, they are often related to a specific situation and disappear with treatment.

Other conditions that can cause similar symptoms of schizophrenia include:

• Substance abuse. Using illegal drugs, particularly phencyclidine hydrochloride (PCP) and methamphetamine, can cause symptoms of psychosis, including hallucinations or personality changes.
• Bipolar disorder. In severe cases, bipolar disorder can also cause hallucinations and bizarre personality changes.
• Depression that has features of psychosis.
• Poor interaction of combined medications. Taking several prescription medications that interact with each other can lead to hallucinations and other symptoms that are similar to the positive symptoms of schizophrenia.

Even if you do not have schizophrenia, you need to see a health professional if you experience any symptoms that are similar to those of the positive symptoms of schizophrenia.