AddictionAddiction is generally a neuropsychological disorder defining pervasive and intense urge to engage in maladaptive behaviors providing immediate sensory rewards (e.g. consuming drugs, excessively gambling), despite their harmful consequences. Dependence is generally an addiction that can involve withdrawal issues. Addictive disorder is a category of mental disorders defining important intensities of addictions or dependences, which induce functional disabilities. There are no agreed definitions on these terms – see section on 'definitions'.
Alcohol (drug)Alcohol, sometimes referred to by the chemical name ethanol, is a depressant drug that is the active ingredient in drinks such as beer, wine, and distilled spirits (hard liquor). It is one of the oldest and most commonly consumed recreational drugs, causing the characteristic effects of alcohol intoxication ("drunkenness"). Among other effects, alcohol produces happiness and euphoria, decreased anxiety, increased sociability, sedation, impairment of cognitive, memory, motor, and sensory function, and generalized depression of central nervous system (CNS) function.
Alcohol dependenceAlcohol dependence is a previous (DSM-IV and ICD-10) psychiatric diagnosis in which an individual is physically or psychologically dependent upon alcohol (also chemically known as ethanol). In 2013, it was reclassified as alcohol use disorder in DSM-5, which combined alcohol dependence and alcohol abuse into this diagnosis.
Physical dependencePhysical dependence is a physical condition caused by chronic use of a tolerance-forming drug, in which abrupt or gradual drug withdrawal causes unpleasant physical symptoms. Physical dependence can develop from low-dose therapeutic use of certain medications such as benzodiazepines, opioids, antiepileptics and antidepressants, as well as the recreational misuse of drugs such as alcohol, opioids and benzodiazepines. The higher the dose used, the greater the duration of use, and the earlier age use began are predictive of worsened physical dependence and thus more severe withdrawal syndromes.
Drug withdrawalDrug withdrawal, drug withdrawal syndrome, or substance withdrawal syndrome, is the group of symptoms that occur upon the abrupt discontinuation or decrease in the intake of pharmaceutical or recreational drugs. In order for the symptoms of withdrawal to occur, one must have first developed a form of drug dependence. This may occur as physical dependence, psychological dependence or both. Drug dependence develops from consuming one or more substances over a period of time.
PregabalinPregabalin, sold under the brand name Lyrica among others, is an anticonvulsant, analgesic and anxiolytic medication used to treat epilepsy, neuropathic pain, fibromyalgia, restless leg syndrome, opioid withdrawal and generalized anxiety disorder (GAD). Pregabalin also has antiallodynic properties. Its use in epilepsy is as an add-on therapy for partial seizures. It is a gabapentinoid medication and acts by inhibiting certain calcium channels. When used before surgery, it reduces pain but results in greater sedation and visual disturbances.
Substance dependenceSubstance dependence, also known as drug dependence, is a biopsychological situation whereby an individual's functionality is dependent on the necessitated re-consumption of a psychoactive substance because of an adaptive state that has developed within the individual from psychoactive substance consumption that results in the experience of withdrawal and that necessitates the re-consumption of the drug. A drug addiction, a distinct concept from substance dependence, is defined as compulsive, out-of-control drug use, despite negative consequences.
OpioidOpioids are substances that act on opioid receptors to produce morphine-like effects. Medically they are primarily used for pain relief, including anesthesia. Other medical uses include suppression of diarrhea, replacement therapy for opioid use disorder, reversing opioid overdose, and suppressing cough. Extremely potent opioids such as carfentanil are approved only for veterinary use. Opioids are also frequently used non-medically for their euphoric effects or to prevent withdrawal.
NicotineNicotine is a naturally produced alkaloid in the nightshade family of plants (most predominantly in tobacco and Duboisia hopwoodii) and is widely used recreationally as a stimulant and anxiolytic. As a pharmaceutical drug, it is used for smoking cessation to relieve withdrawal symptoms. Nicotine acts as a receptor agonist at most nicotinic acetylcholine receptors (nAChRs), except at two nicotinic receptor subunits (nAChRα9 and nAChRα10) where it acts as a receptor antagonist. Nicotine constitutes approximately 0.
HallucinogenHallucinogens 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. The word hallucinogen is derived from the word hallucination. The term hallucinate dates back to around 1595–1605, and is derived from the Latin hallūcinātus, the past participle of (h)allūcināri, meaning "to wander in the mind.