Schizophrenia develops in about 1 in 100 people, equally in men and women. Age of onset is usually 15-25 in men and 25-35 in women.  Symptoms include hallucinations (such as hearing voices), false ideas (delusions), disordered thoughts and problems with feelings, behavior and motivation. In some individuals the disorder comes back or persists long-term but some people have just one episode of a disorder.  Prognosis is not necessarily poor; it is possible to achieve full control of symptoms and restoration of functioning in roughly 20% of patients.


How is the diagnosis made?

Some of the symptoms that occur in schizophrenia also occur in other mental health conditions such as depression, anxiety, mania or obsessive-compulsive disorder. Therefore, the diagnosis may not be clear at first. Moreover, not all symptoms are present in all cases. Different forms of schizophrenia occur depending upon the main symptoms that develop. For example, patients with paranoid schizophrenia mainly have delusions that people are trying to harm them. In contrast, some patients mainly have negative symptoms, that is decreased social contacts, apathy, emotional withdrawal.  In a majority of cases there is a mix of positive, disorganized and negative symptoms. In approximately 15% of patients, typical schizophrenic symptoms co-occur with obsessive-compulsive symptoms. This condition is defined as schizo-obsessive disorder (link to the book).


How do symptoms develop?

Sometimes symptoms develop quickly over a few weeks or so. Family and friends may recognize that the person has a mental health problem. Sometimes symptoms develop slowly over months and the person may gradually become withdrawn, lose friends, jobs before the condition is recognized. Identification of initial symptoms of the disorder and correct diagnosis is challenging and required a great deal of clinical experience.  


The exact cause is not known. It is thought that the balance of certain brain chemicals (neurotransmitters), primarily dopamine, serotonin, glutamate is altered. Neurotransmitters are needed to pass messages between brain cells. An altered balance of these neurochemicals may cause the symptoms. For example, excessive dopamine neurotransmission in certain brain areas, is thought to account for the development of delusions and hallucinations. Antipsychotic agents are effective because they attenuate dopamine hyperactivity. 

Genetic (hereditary) factors are thought to be important. For example, a close family member of someone with schizophrenia has a 1 in 10 chance of also developing the condition. This is higher the normal chance. In addition, family members may have attenuated forms of the disorder, so-called schizotypal disorder.  These family members rarely develop schizophrenia. Some family members may have obsessive-compulsive traits (e.g., excessive cleanness, strive for order and symmetry, checking). Identification of these personality traits is important, since they may also be present in a patient with schizophrenia, affecting treatment and prognosis (link to the abstract of our family paper).




Positive symptoms

  • Delusions. These are false beliefs that a person has and most people from the same culture would agree that they are wrong. Even when the wrongness of the belief is explained, a person with schizophrenia is convinced that they are true. For example, a person with schizophrenia may believe that neighbors are spying on them with cameras in every room, or that people are plotting to kill them, or there is a conspiracy about them. These are only a few examples and delusions can be about anything.

  • Hallucinations. This means hearing, seeing, feeling, smelling, or tasting things that are not real. Hearing voices is the most common. Some people with schizophrenia hear voices that provide a running commentary on their actions, argue with them, or repeat their thoughts. The voices often say things that are rude, aggressive, unpleasant, or give orders that must be followed. Some people with schizophrenia appear to talk to themselves as they respond to the voices. People with schizophrenia believe that the hallucinations are real.

  • Disordered thoughts. Thoughts may become jumbled or blocked. Thought and speech may not follow a normal logical pattern. For example, some people with schizophrenia have one or more of the following:

    • Thought echo. This means the person hears his or her own thoughts as if they were being spoken aloud.

    • Knight's-move thinking. This means the person moves from one train of thought to another that has no apparent connection to the first.

    • Some people with schizophrenia may invent new words (neologisms), repeat a single word or phrase out of context (verbal stereotypy), or use ordinary words to which they attribute a different, special meaning (metonyms).

Symptoms called disorders of thought possession may also occur. These include:

  • Thought insertion. This is when someone believes that the thoughts in their mind are not their own and that they are being put there by someone else.

  • Thought withdrawal. This is when someone believes that thoughts are being removed from their mind by an outside agency.

  • Thought broadcasting. This is when someone believes that their thoughts are being read or heard by others.

  • Thought blocking. This is when there is a sudden interruption of the train of thought before it is completed, leaving a blank. The person suddenly stops talking and cannot recall what he or she has been saying.










Negative symptoms

Negative symptoms include the following

  • Lack of motivation. Everything seems an effort - for example, tasks may not be finished, concentration is poor, there is loss of interest in social activities and the person often wants to be alone.

  • Few spontaneous movements and much time doing nothing.

  • Facial expressions do not change much and the voice may sound monotonous.

  • Changed feelings. Emotions may become flat. Sometimes the emotions may be odd, such as laughing at something sad. Other strange behaviours sometimes occur.

Negative symptoms can make some people neglect themselves. They may not care to do anything and appear to be wrapped up in their own thoughts. Negative symptoms can also lead to difficulty with education, which can contribute to difficulties with employment.


Treatments for schizophrenia

Antipsychotic medications

The main medicines used to treat schizophrenia are called antipsychotics. They work by altering the balance of neurotransmitters, primarily dopamine and serotonin. Antipsychotic medication is used to relieve the symptoms. They tend to work best to ease delusions and hallucinations and tend not to work so well to ease negative symptoms. Antipsychotic medicines are also used to prevent recurring episodes of symptoms (relapses). Therefore, antipsychotic medication is usually taken on a long-term basis. There are various antipsychotic medicines and different ones may be used in different circumstances. They are broadly divided into two categories:

  • Newer or atypical antipsychotics. These are sometimes called second-generation antipsychotics and include amisulpride (Solian), aripiprazole (Abilify), olanzapine (Zyprexa), quetiapine (Seroquel), risperidone (Respiridal). One of these medicines is commonly used first-line for new cases. This is because they seem to have a good balance between chance of success and the risk of side-effects.

  • Older typical well-established antipsychotics. These are sometimes called first-generation antipsychotics and include chlorpromazine (Largactil), haloperidol (Halidol), sulpiride (Modal).

  • Clozapine (Leponex) is reserved only to those who do not respond to “regular” antipsychotic.

A major difference between these two groups is a side effect profile. Older medications induce more motor disorders in substantial proportion of patients, such as tremor, dystonia, leg restlessness   

A good response to antipsychotic medication occurs in about 7 in 10 patients. However, symptoms may take 2-4 weeks to ease after starting medication and it can take several weeks for full improvement. Even when symptoms ease, antipsychotic medication is normally continued long-term. This aims to prevent relapses, or to limit the number and severity of relapses. However, if you only have one episode of symptoms that clears completely with treatment, one option is to try coming off medication after 1-2 years. Your doctor will advise.

Side-effects from antipsychotic medicines

The different antipsychotic medicines can have different types of side-effects. Also, sometimes one medicine causes side-effects in some people and not in others. Therefore, sometimes more than one treatment trial is needed to figure out what antipsychotic is best suited to an individual.

The following are the main side-effects that sometimes occur.

  • Common side-effects include: dry mouth, blurred vision, flushing and constipation. These may ease off when you get used to the medicine.

  • Drowsiness (sedation) is also common but may be an indication that the dose is too high. A reduced dose may be an option.