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Ketamine
Ketamine is a dissociative anesthetic used medically for induction and maintenance of anesthesia. It is also used as a recreational drug. It is one of the safest anesthetics, as, in contrast with opiates, ether, and propofol, it suppresses neither respiration nor heart rate. Ketamine is also simple to administer and highly tolerable compared to drugs with similar effects which are flammable, irritating, or even explosive. Ketamine is a novel compound, derived from PCP, created in pursuit of a safer anesthetic with similar characteristics. Ketamine is also used for acute pain management. At anesthetic doses, ketamine induces a state of "dissociative anesthesia", a trance-like state providing pain relief, sedation, and amnesia. The distinguishing features of ketamine anesthesia are preserved breathing and airway reflexes, stimulated heart function with increased blood pressure, and moderate bronchodilation. At lower, sub-anesthetic doses, ketamine is a promising agent for p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Esketamine
Esketamine, also known as (S)-ketamine or S(+)-ketamine, is the ''S''(+) enantiomer of ketamine, is a dissociative hallucinogen drug used as a general anesthetic and as an antidepressant for treatment of depression. It is sold under the brand names Spravato (for depression), Ketanest (for anesthesia), among others. Esketamine is the active enantiomer of ketamine in terms of NMDA receptor antagonism and is more potent than racemic ketamine. It is specifically used as a therapy for treatment-resistant depression (TRD) and for major depressive disorder (MDD) with co-occurring suicidal ideation or behavior. Its effectiveness for depression is modest and similar to that of other antidepressants. Esketamine is used by infusion into a vein for anesthesia and under direct medical supervision as a nasal spray once or twice weekly for depression. Adverse effects of esketamine include dissociation, dizziness, sedation, nausea, vomiting, vertigo, numbness, anxiety, let ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydroxynorketamine
Hydroxynorketamine (HNK), or 6-hydroxynorketamine, is a minor metabolite of the anesthetic, dissociative, and antidepressant drug ketamine. It is formed by hydroxylation of the intermediate norketamine, another metabolite of ketamine. As of late 2019, (2''R'',6''R'')-HNK is in clinical trials for the treatment of depression. The major metabolite of ketamine is norketamine (80%). Norketamine is secondarily converted into 4-, 5-, and 6-hydroxynorketamines (15%), mainly HNK (6-hydroxynorketamine). Ketamine is also transformed into hydroxyketamine (5%). As such, bioactivated HNK comprises less than 15% of a dose of ketamine. Pharmacology In contrast to ketamine and norketamine, HNK is inactive as an anesthetic and psychostimulant. In accordance, it has only very weak affinity for the NMDA receptor (Ki = 21.19 μM and > 100 μM for (2''S'',6''S'')-HNK and (2''R'',6''R'')-HNK, respectively). However, HNK does still show biological activity, having been found to act as a potent and s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arketamine
Arketamine (developmental code names PCN-101, HR-071603), also known as (''R'')-ketamine or (''R'')-(−)-ketamine, is the (''R'')-(−) enantiomer of ketamine. Similarly to racemic ketamine and esketamine, the ''S''(+) enantiomer of ketamine, arketamine is biologically active; however, it is less potent as an NMDA receptor antagonist and anesthetic and thus has never been approved or marketed for clinical use as an enantiopure drug. Arketamine is currently in clinical development as a novel antidepressant. Relative to esketamine, arketamine possesses 4 to 5 times lower affinity for the PCP site of the NMDA receptor. In accordance, arketamine is significantly less potent than racemic ketamine and especially esketamine in terms of anesthetic, analgesic, and sedative-hypnotic effects. Racemic ketamine has weak affinity for the sigma receptor, where it acts as an agonist, whereas esketamine binds negligibly to this receptor, and so the sigma receptor activity of racemic k ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Norketamine
Norketamine, or ''N''-desmethylketamine, is the major active metabolite of ketamine, which is formed mainly by CYP3A4. Similarly to ketamine, norketamine acts as a noncompetitive NMDA receptor antagonist (Ki = 1.7 μM and 13 μM for (''S'')-(+)-norketamine and (''R'')-(–)-norketamine, respectively), but is about 3–5 times less potent as an anesthetic in comparison. Also, similarly again to ketamine, norketamine binds to the μ- and κ-opioid receptors. Relative to ketamine, norketamine is much more potent as an antagonist of the α7-nicotinic acetylcholine receptor, and produces rapid antidepressant effects in animal models which have been reported to correlate with its activity at this receptor. However, norketamine is about 1/5 as potent as ketamine as an antidepressant in mice as per the forced swim test, and this seems also to be in accordance with its 3–5-fold reduced comparative potency ''in vivo'' as an NMDA receptor antagonist. Norketamine is metabolized into dehyd ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NMDA Receptor Antagonists
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 animals and humans; the state of anesthesia they induce is referred to as dissociative anesthesia. Several synthetic opioids function additionally as NMDAR-antagonists, such as pethidine, levorphanol, methadone, dextropropoxyphene, tramadol and ketobemidone. Some NMDA receptor antagonists, such as ketamine, dextromethorphan (DXM), phencyclidine (PCP), methoxetamine (MXE), and nitrous oxide (N2O), are sometimes used as recreational drugs, for their dissociative, hallucinogenic, and euphoriant properties. When used recreationally, they are classified as dissociative drugs. Uses and effects NMDA receptor antagonists induce a state called dissociative anesthesia, marked by catalepsy, amnesia, and analgesia. Ketamine is a favored anesthetic for emergency patients with unknown medica ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dehydronorketamine
Dehydronorketamine (DHNK), or 5,6-dehydronorketamine, is a minor metabolite of ketamine which is formed by dehydrogenation of its metabolite norketamine. Though originally considered to be inactive, DHNK has been found to act as a potent and selective negative allosteric modulator of the α7-nicotinic acetylcholine receptor ( IC50 = 55 nM). For this reason, similarly to hydroxynorketamine (HNK), it has been hypothesized that DHNK may have the capacity to produce rapid antidepressant effects. However, unlike ketamine, norketamine, and HNK, DHNK has been found to be inactive in the forced swim test (FST) in mice at doses up to 50 mg/kg. DHNK is inactive at the α3β4-nicotinic acetylcholine receptor (IC50 > 100 μM) and is only very weakly active at the NMDA receptor (Ki = 38.95 μM for (''S'')-(+)-DHNK). It can be detected 7–10 days after a modest dose of ketamine, and because of this, is useful in drug detection assays. See also * Arketamine * Esketamine Esketamine, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Recreational Drug
Recreational drug use indicates 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 by modifying the perceptions and emotions of the user. When a psychoactive drug enters the user's body, it induces an Substance intoxication, intoxicating effect. Generally, recreational drugs are divided into three categories: depressants (drugs that induce a feeling of relaxation and calmness); stimulants (drugs that induce a sense of energy and alertness); and hallucinogens (drugs that induce perceptual distortions such as hallucination). In popular practice, recreational drug use generally is a tolerated social behaviour, rather than perceived as the medical condition of self-medication. However, heavy use of some drugs is Social stigma, socially stigmatized. Many people also use prescribed and controlled depressants such as opioids, as well as opiates and benzodiazepines. Common recreational dr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dissociative
Dissociatives, colloquially dissos, are a subclass of hallucinogens which distort perception of sight and sound and produce feelings of detachment – dissociation – from the environment and/or self. Although many kinds of drugs are capable of such action, dissociatives are unique in that they do so in such a way that they produce hallucinogenic effects, which may include dissociation, a general decrease in sensory experience, hallucinations, dream-like states or anesthesia. Some of these substances, which are nonselective in action and affect the dopamine and/or opioid systems, may be capable of inducing euphoria or symptoms which are more akin to the effects of certain “ hard drugs” or common drugs of abuse. This is likely why dissociatives are considered to be addictive with a fair to moderate potential for abuse, unlike psychedelics. Despite some dissociatives, such as phencyclidine (PCP) possessing stimulating properties, most dissociatives seem to have a general d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dissociative Hallucinogen
Dissociatives, colloquially dissos, are a subclass of hallucinogens which distort perception of sight and sound and produce feelings of detachment – dissociation – from the environment and/or self. Although many kinds of drugs are capable of such action, dissociatives are unique in that they do so in such a way that they produce hallucinogenic effects, which may include dissociation, a general decrease in sensory experience, hallucinations, dream-like states or anesthesia. Some of these substances, which are nonselective in action and affect the dopamine and/or opioid systems, may be capable of inducing euphoria or symptoms which are more akin to the effects of certain “hard drugs” or common drugs of abuse. This is likely why dissociatives are considered to be addictive with a fair to moderate potential for abuse, unlike psychedelics. Despite some dissociatives, such as phencyclidine (PCP) possessing stimulating properties, most dissociatives seem to have a general depre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antidepressant
Antidepressants are a class of medication used to treat major depressive disorder, anxiety disorders, chronic pain conditions, and to help manage addictions. Common side-effects of antidepressants include dry mouth, weight gain, dizziness, headaches, sexual dysfunction, and emotional blunting. There is a slight increased risk of suicidal thinking and behavior when taken by children, adolescents, and young adults. Discontinuation syndrome may occur after stopping any antidepressant which resembles recurrent depression. Some research regarding the effectiveness of antidepressants for depression in adults has found benefits, whilst other research has not. Evidence of benefit in children and adolescents is unclear. The twenty-one most commonly prescribed antidepressant medications are more effective than placebo for the short-term (acute) treatments of adults with major depressive disorder. There is debate in the medical community about how much of the observed effects of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
