Psychiatry is a branch of medicine that studies and treats mental illness. While any physician may encounter and treat mental illness, psychiatrists are more extensively trained in the differential diagnosis (distinguising various forms) of mental illness and are professionally required to keep up to date on the newest treatment modalities for mental illness.

Practice of psychiatry

The field of psychiatry itself can be subdivided into various subfields, and many institutional psychiatrists only practice one of these fields. Acute psychiatry (psychoses, liaison psychiatry and crisis intervention), mood disorders, long-term care, substance and alcohol abuse and learning difficulties are amongst the more prominent subfields of psychiatry. Pediatric psychiatry focuses on children and adolescents.

A patient (or, euphemistically, a "client") comes under the care of a psychiatrist through various means. This may be by self-referral (the most common form in the United States,) referral by a primary care physician, hospital medical staff, sectioning or involuntary commitment by law or after a court order. In all circumstances, the psychiatrist makes an assessment of the patient's mental and somatic (general medical) functioning, through conversation with the patient and/or by obtaining information from relatives and associates, carers, law enforcement personnel or the nursing staff and therapists of institutions (if the client is admitted or sectioned). Physical examination is usually performed to establish or exclude physical illness and identify subtle signs of self-harm, and blood tests and medical imaging may be performed, which may lead to the involvement of other medical specialists in a patient's care (e.g. if AIDS is diagnosed).

Not all mental conditions are treated with medication. Psychotherapy and cognitive behavioral therapy may be used in many conditions, either exclusively or in combination with medication. In general, commencing a patient on medication requires that the patient agrees to this treatment (although in many countries the law provides overriding circumstances) and that the patient will remain compliant with the treatment. In addition, many psychiatric medications may have side-effects and therefore the patient may require ongoing monitoring (e.g. a frequent full blood count for patients on clozapine, an antipsychotic, or monitoring of serum levels of lithium in patients on lithium salts); many psychiatric hospitals and institutions have facilities for therapeutic drug monitoring. Electroconvulsive therapy is occasionally administered in serious and disabling conditions that are unresponsive to pharmacotherapy.

Psychiatric patients can be broadly grouped into inpatients and outpatients. Outpatients live in their normal community, and come in periodically to the psychiatrist’s office for care, typically for a 30-50 minute appointment. These office sessions generally involve an update in condition and assessment, medication management, and in some cases psychotherapy. The length of time between sessions varies widely, depending on the severity of the condition and the patient’s stability.

Inpatients are confined to a hospital where they receive their psychiatric care (voluntarily in the majority of cases, but sometimes involuntarily in severe or dangerous cases). In a hospital setting, patients can be more carefully monitored, treated more rapidly, and better protected from self-harm (and in rarer cases, harming others). Hospitalized patients are increasingly being managed in a multidisciplinary fashion, where nursing staff, occupational therapists, psychotherapists, social workers and other health care professionals offer their input in the care for a patient. Historically, particularly before the advent of psychiatric medication, hospital stays averaged six months or more with a large number of cases requiring hospitalization for many years. Today the average hospital stay is on the order of two to three weeks, with only a small number of cases requiring long term hospitalization. Upon release from the hospital, inpatients typically become outpatients.

The DSM system

The Diagnostic and Statistical Manual of Mental Disorders, presently in its fourth revised (IV-TR, 2000) edition, systemises psychiatric diagnosis in five axes:

Axis I: potentially transient conditions
Axis II: underlying pervasive or personality conditions, as well as developmental or learning disorders
Axis III: any nonpsychiatric medical condition ("somatic")
Axis IV: social functioning and impact of symptoms
Axis V: Global Assessment of Functioning (on a scale from 100 to 0)
Common Axis I disorders include depression, anxiety disorders, bipolar disorder, and schizophrenia. Common Axis II disorders include borderline personality disorder, schizotypal personality disorder, avoidant personality disorder, and antisocial personality disorder.

Contrast with psychology

Psychiatry is practiced by psychiatrists, medical doctors specializing in mental illness who may prescribe drugs. Psychiatrists evaluate patients from a biopsychosocial perspective before prescribing treatment. In contrast, psychology is the broader study of human behaviour and thought processes, not just in the context of mental health. Clinical psychologists specialize in mental health and have extensive training in psychotherapy and psychological testing. In most cases they are not permitted by law to prescribe drugs, although they sometimes provide the patient's psychiatrist with feedback. (In the United States, psychotherapists are permitted by law to prescribe psychotropic medications in the Department of Defense, Guam, New Mexico, and Louisiana, but must complete a postdoctoral training program in clinical psychopharmacology and practicum, and pass a licensing examination prior to doing so.) Today most psychotherapy is performed by clinical psychologists rather than psychiatrists.

Professional requirements

In the United States, psychiatrists are board certified as specialists in their field. Physicians wishing to become board certified psychiatrists will practice as residents for four years, learning the specialty before taking the psychiatry boards. In the United Kingdom, people work as a senior house officer (SHO) in psychiatry for 2-3 year while sitting postgraduate exams, after which they may apply for a specialist registrar post. In other countries, similar rules usually apply.

History

Psychiatric illnesses were for some time characterised as disorders of function of the mind rather than the brain, although the distinction is not always obvious. In the current state of knowledge this distinction does not always hold true, as many psychiatric conditions have physical etiologies.

For a long period of history, neurology and psychiatry were a single discipline, and following their division the tremendous advances in neurosciences (especially in genetics and neuroimaging) recently are bringing areas of the two disciplines back together. Indeed, in a 2002 review article in the American Journal of Psychiatry, Professor Joseph B. Martin, Dean of Harvard Medical School and a neurologist by training, wrote that "the separation of the (neurological versus psychiatric disorders) is arbitrary, often influenced by beliefs rather than proven scientific observations. And the fact that the brain and mind are one makes the separation artificial anyway" (Martin 2002).

Psychiatry was at first a pragmatic discipline that was part of general medicine, combining medicine and practical psychology. The work of Emil Kraepelin laid the foundations of scientific psychiatry, but was derailed by the psychoanalytic theories of Sigmund Freud. For many years, Freudian theories dominated psychiatric thinking.

The discovery of lithium carbonate as a treatment for bipolar disorder (and shortly thereafter after by the development of typical antipsychotics for treatment of schizophrenia,) followed by the development of fields such as molecular biology and tools such as brain imaging has led to psychiatry re-discovering its origins in physical and observational medicine without losing sight of its humane dimension.

Anti-psychiatry:

Unlike most other areas of medicine, there is a politicised anti-psychiatry movement opposed to the practices of, and in some cases the existence of, psychiatry. Some opponents of psychiatry state that selective financing by large multinational drug companies of both high ranking professional psychiatrists, research and educational material has led the practice of psychiatry to be subversively, and in some cases inhumanely, misled.

One of the chief complaints of the anti-psychiatry movement is that no cause of mental illness, verifiable by testing for a specific medical pathology, has ever been found, in complete contrast with most medical diseases. There are a number of people trained in the field who have stated that physical tests cannot distinquish between a normal person and a mentally ill person. In lieu of scientifically defined clinical pathologies, critics contend, psychiatrists rely upon a notion of mental illness often referred to as the chemical imbalance theory (although this term is most commonly used by opponents to psychiatry).

There are also criticisms based on what is perceived as political motivations on the part of psychiatrists as opposed to objective scientific criteria. An example often cited is the removal of homosexuality from the list of mental illnesses in the DSM. Thus, some critics contend a mental illness label such as schizophrenia has no etiology and is only a matter of opinion. If the addition or removal of mental illnesses from the DSM is politically based, then the DSM can not be held by all as an objective standard. However, it is possible to argue that even if the removal or addition of psychiatric conditions to/from the DSM has been politically motivated, the initial inclusion or exclusion may have been a result of politics, creating something of an equalization effect. Morever, many would hold it logically fallacious to argue all DSM diagnoses are categorically invalid simply because one or some may be politically motivated or otherwise invalid.

Also, some people criticize the psychiatric profession for treatments that transition into and out of usage. An example is electroconvulsive therapy (ECT), which the psychiatric profession considered a barbarous practice during the 1970s and 1980s, only to be revived recently as a treatment for clinical depression. (Psychiatrists point out that ECT as practiced today bears little to no resemblance to horror stories from the past or popular depictions such as in One Flew Over the Cookoo’s Nest, and remains the most effective treatment for some severe cases.)

A few prominent critics of psychology and mental illness in general include Thomas Szasz, the author of "The Myth of Mental Illness", who founded an organization in 1969 together with the Church of Scientology (though soon afterwards he disavowed further association with them) called the Citizens Commission on Human Rights (CCHR), Peter Breggin, the author of Prozac Backlash, as well as other books criticizing the use of psychiatric drugs, Elliott Valenstein, Douglas C. Smith, Bruce Levine, and David Keirsey. In the United States and some other countries, Scientologists have been among the most vocal and prominent opponents of psychiatry in recent decades; members believe that psychiatry is a corrupt profession and present scientology as an alternative.

Other criticisms of psychiatry

Others, probably a considerably larger number than those who oppose psychiatry altogether, still have problems with a number of aspects of the profession as practiced today. Many believe that psychiatrists have an incentive and tendency to over-diagnose disorders and to prescribe medication in cases where it is not necessary (or in some cases even when medically contraindicated.) Many critics question the current DSM diagnostic labels, finding some or all labels arbitrary, vague, and/or lacking in firm biological basis, leading some to describe them as pseudoscientific.

Drug companies spend enormous amounts of money marketing psychiatric drugs. There is evidence this leads some psychiatrists to prescribe advertised drugs instead of more appropriate, better, or cheaper drugs (or prescribing them when drugs are not needed at all). The training and techniques of psychiatrists can vary substantially, according to critics, and patients often have to switch psychiatrists a few times before they find one they are satisfied with. Critics also contend training is unduly influenced by the drug industry.

Misdiagnosis (one common example, unipolar depression instead of bipolar depression) remains a problem in some cases, prolonging the suffering for those patients. Also, different individuals respond differently to a given psychiatric drug; this can lead to some patients experiencing a prolonged trial-and-error process.