Psychosis is a term used to describe an array of signs and symptoms suggesting a form of thinking that breaks from reality. Psychosis is not pathognomonic (a sign or symptom specific to a disease or condition) of psychiatric illness. It is a nonspecific cluster of signs and symptoms that may occur in a broad array of medical, neurologic and surgical disorders, or as a consequence of pharmacologic treatment, substance abuse or the withdrawal of drugs and alcohol.


Psychosis is a syndrome. The predominant characteristics of this syndrome are used in determining its classification of either organic or functional mental disorders.

Psychosis can be due to organic disorders (like thyroid abnormalities) which cause structural defects or physiologic dysfunction of the brain. There is substantial evidence that there are chemical abnormalities in the brains of people with this problem.

Psychosis is characterized by an adherence either to fixed, false beliefs outside the normal range of a person's subculture, or by a hallucinatory experience or by what is known as thought disorder: thinking that does not follow any rational line. False beliefs that cause a person to suffer, produce conflict with others or render a person unable to comfortably adapt to the demands of life, are delusions if they are not relinquished when the person is presented with adequate evidence to the contrary. This definition allows for idiosyncrasy and for differences in the beliefs of a person's subculture from those of the majority of the population.

Types Of Psychoses

The major types of psychoses are:

Organic Brain Disorders. One of the most common signs of organic brain disorders is delirium. Specifically, delirium involves disturbances of attention, memory, and orientation. A demented person is usually disoriented in terms of time and space, and has incoherent thoughts and speech.

Psychosis Due to Drugs and Alcohol. Substance abuse is one of the most common causes of psychosis. Combining alcohol and drugs such as barbiturates may be fatal. Inappropriate use of medications can cause brain damage so severe that the person is left in permanent "vegetative" coma.

Some of the most frightening and disorienting mental reactions can come from ingestion of the hallucinogenic drugs: lysergic acid diethylamide (LSD), mescaline, psilocybin or phencyclidine (PCP - also called "angel dust"), and occasionally, marijuana or hashish. The consequences include panic, anxiety, fear of "losing your mind," fearful disorientation, delusions, illusions and hallucinations.

Mania. Sometimes, but not always, alternating with periods of depression, mania includes episodes of mood elevation. During a manic episode, a person will be excessively optimistic, may show increased energy, have excessive drug and alcohol use, have less need for sleep, may be excessively talkative, and show poor judgment or lack of common sense to the point of making dangerous or unusual decisions.

Schizophrenia. About 1 percent of the U.S. population has schizophrenia. Schizophrenia is a disease of disorganization of social and psychological function, including social withdrawal and eccentric behavior. The psychosis experienced in schizophrenia can take many forms. Commonly, a person with the disease will hear voices that offer a running commentary of their activities. In more extreme, cases these voices can be damaging and very frightening. People with schizophrenia can also experience extreme paranoia which may cause a person to seclude themselves to avoid others from ‘spying’ on them. The paranoia a person with schizophrenia experiences can also make a person believe that they have a tracking device within their own body and lead them to try to remove it, often with disastrous medical consequences.


Persons with psychoses, whatever the cause of their problem, may exhibit one or more of the following characteristics:

Disordered Thinking. Most commonly, people with thought disorders suffer delusions, i.e., false beliefs that cannot be shaken by the application of a logical argument.

Disordered Perception. An example of disordered perception is a hallucination, where there is no contribution from the senses to be misinterpreted, but rather the impression of something existing that is not actually there. Commonly, it is hearing, seeing, feeling or smelling things that are not there. Auditory and visual hallucinations can be a sign of psychosis due to a psychiatric disorder, but they may be evidence of brain tumors or a reaction to poison or drugs.

Language Disorders. A psychotic person may be incapable of answering a question directly or sticking to one topic. Psychotic people may also stop talking in mid sentence and abruptly fall silent. Another clue to psychosis is an excess of literal or concrete thinking, such as that shown in the patient who, upon being asked what was on his mind, replied, "My skull."

Disturbance of Affect: Many people with psychosis show inappropriate or labile affect; that is, their apparent emotion is either not consistent with what they are thinking, or fluctuates much more rapidly than normal. Thus, a psychotic person may laugh, cry, and show rage, all within a few minutes.


A physician will take a complete medical history and perform a physical exam. He or she may also suggest blood or other tests to help diagnose the condition.


A physician (often a psychiatrist) will help develop a treatment plan that best serves the individual. Medications are often one component of that treatment plan.

The drugs used to treat psychoses are often referred to as major tranquilizers. Their principal action, however, is not to cause tranquility or sedation, but to reduce or completely eliminate psychotic symptoms and behavior. These anti-psychotic drugs appear to act by blocking the chemical receptors in the brain that normally link up via the chemical nerve messenger called dopamine. Medications may include chlorpromazine (Thorazine) or Haloperidol (Haldol).

Some of the older anti-psychotic drugs for schizophrenia are very effective, but they also cause a range of side effects such as dry mouth. The most troublesome side effect of the antipsychotic drugs is tardive dyskinesia, involuntary and abnormal facial movements such as grimacing, sticking out the tongue and sucking motions. This side effect can occur in 15 to 20 percent of all patients, and is often associated with the dose and length of time the patient is on the drug. It may disappear after several months if the drug is discontinued as soon as the involuntary movements begin. Tardive dyskinesia may be controlled by the medication Cogentin. Fortunately the newer atypical antipsychotic medications that are now available have much lower risk of causing this or other movement disorders.