The following is a list of mental disorders as defined at any point by the Diagnostic and Statistical Manual of Mental Disorders (DSM) or the International Classification of Diseases (ICD). A mental disorder, also known as a mental illness, mental health condition, or psychiatric disorder, is characterized by a pattern of behavior or mental function that significantly impairs personal functioning or causes considerable distress. [1]
The DSM, a classification and diagnostic guide published by the American Psychiatric Association, includes over 450 distinct definitions of mental disorders. [2] Meanwhile, the ICD, published by the World Health Organization, stands as the international standard for categorizing all medical conditions, including sections on mental and behavioral disorders. [3]
Revisions and updates are periodically made to the diagnostic criteria and descriptions in the DSM and ICD to reflect current understanding and consensus within the mental health field. The list includes conditions currently recognized as mental disorders according to these systems. There is ongoing debate among mental health professionals, including psychiatrists, about the definitions and criteria used to delineate mental disorders. There is particular concern over whether certain conditions should be classified as "mental illnesses" or might more accurately be described as neurological disorders or in other terms. [4]
Phencyclidine or phenylcyclohexyl piperidine (PCP), also known in its use as a street drug as angel dust among other names, is a dissociative anesthetic mainly used recreationally for its significant mind-altering effects. PCP may cause hallucinations, distorted perceptions of sounds, and violent behavior. As a recreational drug, it is typically smoked, but may be taken by mouth, snorted, or injected. It may also be mixed with cannabis or tobacco.
Recreational drug use is the use of one or more psychoactive drugs to induce an altered state of consciousness, either for pleasure or for some other casual purpose or pastime. When a psychoactive drug enters the user's body, it induces an intoxicating effect. Recreational drugs are commonly divided into three categories: depressants, stimulants, and hallucinogens.
Psychopharmacology is the scientific study of the effects drugs have on mood, sensation, thinking, behavior, judgment and evaluation, and memory. It is distinguished from neuropsychopharmacology, which emphasizes the correlation between drug-induced changes in the functioning of cells in the nervous system and changes in consciousness and behavior.
Club drugs, also called rave drugs or party drugs, are a loosely defined category of recreational drugs which are associated with discothèques in the 1970s and nightclubs, dance clubs, electronic dance music (EDM) parties, and raves in the 1980s to today. Unlike many other categories, such as opiates and benzodiazepines, which are established according to pharmaceutical or chemical properties, club drugs are a "category of convenience", in which drugs are included due to the locations they are consumed and/or where the user goes while under the influence of the drugs. Club drugs are generally used by adolescents and young adults.
A sedative or tranquilliser is a substance that induces sedation by reducing irritability or excitement. They are CNS depressants and interact with brain activity causing its deceleration. Various kinds of sedatives can be distinguished, but the majority of them affect the neurotransmitter gamma-aminobutyric acid (GABA). In spite of the fact that each sedative acts in its own way, most produce relaxing effects by increasing GABA activity.
Depressants, colloquially known as "downers" or central nervous system (CNS) depressants, are drugs that lower neurotransmission levels, decrease the electrical activity of brain cells, or reduce arousal or stimulation in various areas of the brain. Some specific depressants do influence mood, either positively or negatively, but depressants often have no clear impact on mood. In contrast, stimulants, or "uppers", increase mental alertness, making stimulants the opposite drug class from depressants. Antidepressants are defined by their effect on mood, not on general brain activity, so they form an orthogonal category of drugs.
Stimulant psychosis is a mental disorder characterized by psychotic symptoms. It involves and typically occurs following an overdose or several day binge on psychostimulants, though one study reported occurrences at regularly prescribed doses in approximately 0.1% of individuals within the first several weeks after starting amphetamine or methylphenidate therapy. Methamphetamine psychosis, or long-term effects of stimulant use in the brain, depend upon genetics and may persist for some time.
A toxidrome is a syndrome caused by a dangerous level of toxins in the body. It is often the consequence of a drug overdose. Common symptoms include dizziness, disorientation, nausea, vomiting and oscillopsia. It may indicate a medical emergency requiring treatment at a poison control center. Aside from poisoning, a systemic infection may also lead to one. Classic toxidromes are presented below, which are variable or obscured by co-ingestion of multiple drugs.
Emergency psychiatry is the clinical application of psychiatry in emergency settings. Conditions requiring psychiatric interventions may include attempted suicide, substance abuse, depression, psychosis, violence or other rapid changes in behavior.
A drug with psychotomimetic actions mimics the symptoms of psychosis, including delusions and/or delirium, as opposed to only hallucinations. Psychotomimesis is the onset of psychotic symptoms following the administration of such a drug.
NMDA receptor antagonists are a class of drugs that work to antagonize, or inhibit the action of, the N-Methyl-D-aspartate receptor (NMDAR). They are commonly used as anesthetics for humans and animals; the state of anesthesia they induce is referred to as dissociative anesthesia.
Hallucinogens are a large and diverse class of psychoactive drugs that can produce altered states of consciousness characterized by major alterations in thought, mood, and perception as well as other changes. Most hallucinogens can be categorized as either being psychedelics, dissociatives, or deliriants.
Substance-induced psychosis is a form of psychosis that is attributed to substance intoxication. It is a psychosis that results from the effects of various substances, such as medicinal and nonmedicinal substances, legal and illegal drugs, chemicals, and plants. Various psychoactive substances have been implicated in causing or worsening psychosis in users.
3-Methoxyphencyclidine (3-MeO-PCP) is a dissociative hallucinogen of the arylcyclohexylamine class related to phencyclidine (PCP) which has been sold online as a designer drug. It has been used across Europe and the United States. In some cases, consumption has been known to be fatal. It acts mainly as an NMDA receptor antagonist, though it has also been found to interact with the sigma σ1 receptor and the serotonin transporter. The drug does not possess any opioid activity nor does it act as a dopamine reuptake inhibitor.
A psychoactive drug, mind-altering drug, or consciousness-altering drug is a chemical substance that changes brain function and results in alterations in perception, mood, consciousness, cognition, or behavior. The term psychotropic drug is often used interchangeably, while some sources present narrower definitions. These substances may be used medically; recreationally; to purposefully improve performance or alter one's consciousness; as entheogens for ritual, spiritual, or shamanic purposes; or for research, including psychedelic therapy. Some categories of psychoactive drugs, which have therapeutic value, are prescribed by physicians and other healthcare practitioners. Examples include anesthetics, analgesics, anticonvulsant and antiparkinsonian drugs as well as medications used to treat neuropsychiatric disorders, such as antidepressants, anxiolytics, antipsychotics, and stimulant medications. Some psychoactive substances may be used in the detoxification and rehabilitation programs for persons dependent on or addicted to other psychoactive drugs.
The WHO Expert Committee on Drug Dependence (ECDD) is a committee within the World Health Organization (WHO) that consists of a chosen group of independent experts within the field of pharmacology. This committee meets once a year in order to evaluate the effects of psychotic substances towards the public and the properties that cause the addictions, and considering the possible medical or therapeutic benefits and applications.