PSYCHOSIS

Psychosis means abnormal condition of the mind, and is a generic psychiatric term for a mental state often described as involving a "loss of contact with reality". People suffering from psychosis are described as psychotic. Psychosis is given to the more severe forms of psychiatric disorder, during which hallucinations and delusions and impaired insight may occur.  

Some professionals say that the term psychosis is not sufficient as some illnesses grouped under the term "psychosis" have nothing in common.

Psychosis is a loss of contact with reality, usually including false beliefs about what is taking place or who one is (delusions) and seeing or hearing things that aren't there (hallucinations).

Causes, incidence, and risk factors

A number of substances and medical conditions can cause psychosis, including:

• Alcohol and certain illegal drugs, both during use and during withdrawal
• Brain tumors or cysts
• Dementia (including Alzheimer's disease)
• Degenerative brain diseases, such as Parkinson's disease, Huntington's disease, and certain chromosomal disorders
• HIV and other infections that affect the brain
• Some prescription drugs, such as steroids and stimulants
• Some types of epilepsy
• Stroke

Psychosis is also part of a number of psychiatric disorders, including:

• Bipolar disorder (manic or depressed)
• Delusional disorder
• Depression with psychotic features
• Personality disorders (schizotypal, shizoid, paranoid, and sometimes borderline)
• Schizoaffective disorder
• Schizophrenia

Symptoms

Psychotic symptoms may include:

• Disorganized thought and speech
• False beliefs that are not based in reality (delusions), especially unfounded fear or suspicion
• Hearing, seeing, or feeling things that are not there (hallucinations)
• Thoughts that "jump" between unrelated topics (disordered thinking)

Signs and tests

Psychiatric evaluation and testing are used to diagnose the cause of the psychosis.

Laboratory testing and brain scans may not be needed, but sometimes can help pinpoint the diagnosis. Tests may include:

• Blood tests for abnormal electrolyte and hormone levels
• Blood tests for syphilis and other infections
• Drug screens
• MRI of the brain
  
  

  Treatment:

Treatment depends on the cause of the psychosis. Care in a hospital is often needed to ensure the patient's safety.

Antipsychotic drugs, which reduce hallucinations and delusions and improve thinking and behavior are helpful, whether the cause is a medical or psychiatric disorder.

• Down-titrate or discontinue antipsychotic doses slowly to decrease risk of relapse or symptom exacerbation.
  
  ATYPICAL ANTIPSYCHOTICS:
   Each atypical antipsychotic has a distinct pharmacologic profile. Unlike conventional antipsychotics, atypical antipsychotics exert their therapeutic effects by antagonizing both the dopamine (D₂) and serotonin (5HT₂) receptors. Aripiprazole, however, functions as a partial agonist at the dopamine D₂ and serotonin 5HT_1A receptors, and as an antagonist at the serotonin 5HT_2A receptor.
  
  Antagonism at other receptors may explain some of the other therapeutic and adverse effects associated with these agents. For example, antagonism of muscarinic receptors (eg, clozapine, olanzapine) may produce anticholinergic-like effects. Antagonism of histamine receptors may cause somnolence and adrenergic α₁receptor antagonism produces orthostatic hypotension (eg, aripiprazole, clozapine, olanzapine,paliperidone, quetiapine, risperidone, ziprasidone).
  
  Atypical antipsychotics have a lower risk of extrapyramidal effects, tardive dyskinesia and prolactin elevation than conventional drugs. However, weight gain, hyperlipidemia, and increased risk of type 2 diabetes are major side effects of this class. Among the atypical antipsychotics, mean weight gain is greatest with clozapine and olanzapine, less with quetiapine, even less with risperidone, and is very low with ziprasidone; all patients should be monitored prior to and during therapy.
  
  Due to the risk of agranulocytosis, clozapine is reserved for patients who can not tolerate or are unresponsive to other antipsychotics.
  
  CONVENTIONAL ANTIPSYCHOTICS: 
  Conventional antipsychotics are dopamine receptor antagonists with a high affinity for dopamine D₂ receptors. They are associated with a high incidence of adverse extrapyramidal effects, tardive dyskinesia, sedation, and hyperprolactinemia that may result in galactorrhea, amenorrhea, or gynecomastia. Among the conventional antipsychotics, mean weight gain is greatest with chlorpromazine and thioridazine.
  
  The conventional antipsychotics can be divided into three groups of phenothiazines on the basis of a variable side chain:
  
  
  Aliphatic phenothiazines (eg, chlorpromazine) are low in potency and more likely to produce sedation, hypotension and anticholinergic effects.
  
  
  Piperidine phenothiazines (eg, thioridazine) produce fewer adverse extrapyramidal effects, which may be attributed to increased antimuscarinic acitivity in the CNS, but can cause depression of cardiac conduction and repolarization.
  
  
  Piperazine phenothiazines (eg, prochlorperazine, fluphenazine, trifluoperazine) have limited antimuscarinic activity, a higher risk of adverse extrapyramidal effects, but a lower incidence of sedation or autonomic side effects.
  
  In general, most phenothiazines have relatively flat dose-response profiles, therefore lower dosages may be as effective and produce less side effects than higher dosages.

Expectations (prognosis)

How well a person does depends on the cause of the psychosis. If the cause can be corrected, the outlook is often good, and treatment with antipsychotic medication may be brief.

Some chronic conditions, such as schizophrenia, may need life-long treatment with antipsychotic medications to control symptoms.

Complications

Psychosis can prevent people from functioning normally and caring for themselves. If the condition is left untreated, people can sometimes harm themselves or others.

Prevention

Prevention depends on the cause. For example, avoiding alcohol abuse prevents alcohol-induced psychosis.