This is a severe mental disorder in which people interpret normality abnormally. This disorder can result in some combination of delusions, hallucinations and extremely disordered thinking and behavior which impairs the daily functioning and this can be disabling. This is a chronic disease and it is requiring lifelong treatment.
This disorder is involving a range of problems with emotions, behavior or thinking (cognition). Signs and symptoms of schizophrenia can vary, but they usually involve disorganized speech, hallucinations or delusions, and they reflect an impaired ability to function. Here are some symptoms of schizophrenia [1,2]:
Negative symptoms: This refers to lack of ability or reduced ability to function normally. For example, the person who suffer from schizophrenia may appear to lack emotion (speaks in a monotone, does not change facial expressions and does not make eye contact) or may neglect personal hygiene. Also this person may have lack ability to experience pleasure, lose interest in everyday activities or socially withdraw.
Delusions: This is a term which is used to false beliefs that are not based in reality. For example, the person may feel that a major catastrophe is about to occur; another person is in love with him or her; he or she has exceptional ability or frame; certain comments or gestures are directed at him or her; and he or she thinks that is being harassed or harmed. This symptom is happening in most people who suffer from schizophrenia.
Extremely disorganized or abnormal motor behavior: This symptom of schizophrenia can show in many different ways such as from childlike silliness to unpredictable agitation. In these people their behavior is not focused on a goal so it is very hard for them to do tasks. This behavior can include useless and excessive movement, a complete lack of response, inappropriate or bizarre posture and resistance to instructions.
Hallucinations: This symptom is involving hearing or seeing things which do not exist. But for the person who suffers from schizophrenia, they have full impact and force of a normal experience. People who suffer from schizophrenia can have any of the mentioned hallucinations but the most common hallucination is hearing voices.
It is not known what is the cause for schizophrenia but there are some studies in which are believed that it is a combination of environment, brain chemistry and genetics which contribute to the development of schizophrenia . Also there are some problems with certain naturally occurring brain chemicals, including neurotransmitters called glutamine and dopamine, which can lead to schizophrenia . There are some neuroimaging studies in which are shown differences in the brain structure and central nervous system of people who suffer from schizophrenia. These studies are not certain about the significance of these changes but they indicate that the schizophrenia is a brain disease.
Risk factors: The exact cause for schizophrenia is not known but there are some factors which can increase the risk of schizophrenia such as
- Taking mind – altering (psychotropic or psychoactive) drugs during teen years and young adulthood 
- Some pregnancy and birth complications, such as malnutrition or exposure to toxins or viruses that may impact brain development 
- Older age of the father
- Increased immune system activation, such as from inflammation or autoimmune diseases 
- Having a family history of schizophrenia 
Complications: When someone suffers from schizophrenia if left it untreated, then it can cause severe problems which can affect every area of their lives. Below are given complications which schizophrenia can cause or be associated with it [1,2]:
- Aggressive behavior, although it is uncommon
- Being victimized
- Health and medical problems
- Social isolation
- Legal and financial problems and homelessness
- Inability to work or attend school
- Abuse of alcohol or other drugs, including tobacco
- Anxiety disorders and obsessive – compulsive disorder (OCD)
- Self – injury 
- Suicide, suicide attempts and thoughts of suicide 
 National Institute of Mental Health. Schizophrenia. Retrieved from www.nimh.nih.gov/health/topics/schizophrenia/index.shtml
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 Dalman C, Allebeck P, Cullberg J, et al. Obstetric complications and the risk of schizophrenia: A longitudinal study of a national birth cohort. Archives Of General Psychiatry. 1999;56(3):234-40.
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