Physical illness adolescent

Both medical iflnesses and medications can cause psychiatric symptoms. The rapidity of onset of psychiatric symptoms is an important clue that a medical cause may be present. Most chronic mental illnesses have a prodromal period, whereas medically based psychiatric symptoms often have a more rapid onset of symptoms. Patients over age 40 at first presentation are more likely to have a medical cause for their psychiatric symptoms because major psychiatric illnesses such as schizophrenia and bipolar disorder usually first present in adolescence or early adulthood. A family history of physical illnesses with a psychiatric component, such as Huntington s chorea or systemic lupus erythematosus, may provide an additional clue. 

Assessment and evaluation of the medically ill child or adolescent is often complicated in various ways by the physical state of the child ... 

Major depression, bipolar syndromes and schizophrenia are common and often severe mental illnesses. All three of these tend to have an onset in late adolescence or young adulthood. Major depression is characterized by persistent low mood and decreased interest and pleasure, as well as physical and psychological symptoms, including sleep disturbance. 

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