Ketamine Intoxication Abuse and Dependence

Ketamine Intoxication Any drug when taken for non-medical purposes then it is termed abused. Today there are very many drugs that are being used for sheer feeling of euphoria the users derive from them. These drugs are common in streets needless to mention some of the drugs that are used in hospitals for medicinal purposes have also been abused greatly. When a particular drug is used for quite a long time for non-medical purpose it becomes very toxic to the body. Substance abuse is a vice that needs to be fought at all costs and from all fronts as it has opened avenues through which lives have been lost. The problems that a person can suffer from long-term drug abuse spring from all the dimensions of a person’s health be it psychological health, mental health, physical health as well as his social relations. A person who is a victim to drug abuse may fail to cater for family needs, school obligations and even fail to have peace within him as he will be having lots of personal and interpersonal conflicts. Drug and substance dependence is commonly known as addiction. Drug or substance dependence is characterized by change in behaviors of a person. Most common behavior being the need to use more quantities of the substance. When a person is dependent on a given substance his life begins to revolve around it and it seems rather hard for him to live without using the substance. The person often suffers such symptoms as withdrawal among other symptoms associated with drug abuse and dependence.

Drug abuse and dependence are dangerous for an individual; however when a person has just began using a particular substance he may be easily helped to quit the habit than when he has used it for so long that he has become dependent on the drug and has begun showing those side effects that are associated with drug dependence. It is also good to note that a person may become dependent on a drug without abusing it. It is also good to note that person may abuse substance for quite a long time without ‘graduating’ to drug dependence.

One of the drugs that are being abused today is the Ketamine. Ketamine is one of the drugs that are very useful in hospitals. It is a perfect example that even some drugs that help us in gaining good health can also be abused. Ketamine is a medication that has been used to treat many illnesses. It is used in medical procedures with humans and other animals and that means it is an accepted medication in hospitals hence can be easily accessed by medical practitioners such as nurses and doctors. In hospitals it is mainly for starting and maintaining general anesthesia especially in scenarios where the patient is to go through intense pain. It also has other uses and these include sedation in intensive care, as a pain killer. It is however commonly used as a painkiller in emergency cases when the patient is allergic to other known drugs used in suppressing pain such as opiate drugs. This drug can be used as treatment of bronchospasm, and as a treatment for complex regional pain syndrome.

Ketamine has been found to work better since its administration does not affect the Respiratory function. For this reason it has become a very valuable anesthetic. However one of the known side effects often associated with administration of ketamine is agitation.

Ketamine is a NMDA noncompetitive Receptor antagonist

Ketamine is an arylcyclohexylamine derivative of phencyclidine. It is also a non-competitive NMDA antagonist. Scientist, Lodge and his colleagues the first showed that ketamine, phencyclidine, related arylcyclohexylamines and congeners were antagonists of excitatory amino acids like aspartate and glutamate in 1983. The early history of the development of ketamine as an anesthetic agent was documented by McCarthy in 1981. Other scientists Corssen and Dundee reviewed the historical introduction of ketamine into human anesthesia and the term dissociative anesthesia in 1990. These scientists found that for ketamine to be used safely in clinical therapies, it had to be tamed.

Low doses of ketamine in humans do not necessarily alter perception in a negative way. Foster gave an IV infusion of three different sub anesthetic doses of ketamine (0.05, 0.1 and 0.2 mg/kg/h) to six patients with Alzheimer’s disease. The patients showed no drowsiness and their reaction times and digit span were unaffected by any of the doses of ketamine used. This study however is rather controversial. This is because NMDA receptors are involved in brain function, including arousal and memory, this study requires further research and explanation because one would have predicted exactly the opposite effects even with the small doses of ketamine used.

Ketamine Intoxication

Ketamine as nicotinic inhibitor

Initially the effect of ketamine blockade on niconitic receptors was unknown. But today after many researches and experiments scientists have shown that racemic ketamine and the isomers inhibits nAChRs and K channels in a concentration-dependent and reversible manner. In an experiment racemic ketamine inhibited nAChRs and K channels, with the anesthetic concentration inducing the half-maximal effect being 1.4 and 300 micrometer, respectively. Only inhibition of the nAChRs was stereo selective. The half-maximal concentrations were 0.8 and 3.6 micrometer for S (+) – and R (-)-ketamine. The K channels were 350 and 70 times less sensitive to the effects of S (+) – and R (-)-ketamine.

Ketamine at concentrations found during clinical anesthesia exerts stereospecific effects on human ganglionic nAChRs but not on voltage-dependent K channels. The results found from this experiment supports the view that ketamine impairs sympathetic ganglionic transmission. Nonspecific effects on voltage-dependent K channels may underlie psychomimetic side effects.

Finally, Dr. Dalal Akoury (MD) is an experienced doctor who has been in the frontline fighting drug addiction. He runs a website that equips readers of better ways to overcome not only drug addiction but also serious health problems that have caused nightmares to the world population. Get in touch with her today and learn more.

Ketamine Intoxication Abuse and Dependence

Phencyclidine (PCP) and Excitatory Actions

September 22, 2014

Phencyclidine (PCP) selectively reduces excitatory actions

Phencyclidine To begin with, it is important to point out to those who have not heard of club drugs yet. These are also known as rave drugs and are often associated with night parties in discotheques. The term club drugs refers to a wide range of substances that are commonly abused by young adults and teens at all-night party clubs and parties. The drugs reported in these scenes are extremely diverse and vary among locales. Overall, they include drugs that have long been abused, such as marijuana and cocaine, and drugs whose abuse is a more recent development. All these drugs are taken with different purposes but most importantly most youths are lured to abuse this drugs by there need to belong. When the party lovers meet and spend time together they will obviously want to do everything together as that will give them a sense of belonging and a ‘family’. Most youths indulge in the use of club drugs not because they really need to but because those they came to club with are using; talk of peer pressure. Some of these drugs are stimulants, some depressants, and some hallucinogens. Most of these club drugs however exhibit multiple pharmacological properties hence cannot be easily categorized. The club drugs are often grouped as;

Designer Drugs

Designer drug is the term used for a drug created by changing the molecular structure of one or more existing drugs to create a new substance. These drugs have no place in the medical field as they have no accepted medical purpose so they can only be used for other purposes other than medical purposes and hence are always abused. As a result, they are synthesized in illicit laboratories. MDMA which is mostly associated with ecstasy is the most sought after and the most commonly abused of the designer drugs. The other designer drugs are considered by users to be inferior substitutes for MDMA and are typically only ingested unknowingly, when present in tablets sold as ecstasy. Examples of other designer drugs are: MDA, MDE, MBDB, DOB, DOM, 2C-B. MDMA and MDA are the most known club drugs and are hence highly used by youths in discotheques.

Hallucinogens

Hallucinogens, also known as psychedelics, refer to a wide range of substances derived from both natural and synthetic sources. In general, hallucinogens distort the user’s sensory perceptions and may also create feelings of euphoria. These effects vary depending on the drug in question. The stronger hallucinogens can exert a powerful effect on a drug user’s thinking and can produce sensory illusions that make it difficult to distinguish between fact and fantasy. In general, hallucinogens do not create a physical dependence, but they can create a psychological dependence. Their consumption also creates a tolerance that is built rapidly within the body. Many drugs that exhibit mild hallucinogenic properties are commonly classified as hallucinogens, including marijuana and MDMA. Drugs that exhibit potent hallucinogenic properties are discussed below, including, LSD, ketamine, peyote/mescaline, and mushrooms.

Depressants

Depressants are also known as sedatives. These drugs commonly abused in the club environment include GHB and Rohypnol. These sedatives are highly potent. As a result, they have earned the title “date rape drugs“. As the name suggests they are very dangerous but unfortunately teens and young men are rocking them like their names depends on them.

Phencyclidine (PCP) selectively reduces excitatory actions

Phencyclidine often shortened as PCP is a major drug of abuse that has anesthetic actions and produces effects that resemble schizophrenia. The mechanism of action of PCP-like drugs has not been established, although specific binding sites in brain have been identified that appear to be pharmacologically relevant. PCP-like drugs selectively antagonize excitation of spinal neurons by N-methyl aspartate commonly abbreviated as NMA. Therefore, the behavioral effects of PCP-like drugs might result from reduced neurotransmission at excitatory synapses utilizing NMA receptors in higher centers of the central nervous system. Until now, this proposed explanation of the behavioral effects of PCP-like drugs is based exclusively on electrophysiological findings.

Phencyclidine

Given that PCP-like drugs produce behavioral effects primarily through antagonism at excitatory synapses utilizing NMA receptors, drugs that are known to antagonize electrophysiological effects of NMA should produce PCP-like behavioral effects. DL-2-Amino-5-phosphonovalerate (AP5) is a potent and highly selective NMA antagonist 8. A procedure for the measurement of catalepsy in pigeons, suitable for studying PCP-like activity of compounds, has been described.

Phencyclidine (PCP) has effects on the NMDA receptor. In an experiment that was done using mice in a laboratory, it was found that Stable N-methyl-D-aspartic acid (NMDA) receptor-mediated currents in cultured mouse hippocampal neurons were evoked by 20 ms pressure pulse applications of L-aspartate, repeatedly applied at 30 or 40 s intervals, to the cell body region of the neuron. In the study a simple model of the blockade, based on the ‘guarded receptor hypothesis’ was used to interpret our data. The model assumes that receptors are maximally activated at the peak of the response with an open probability (Po) approaching 1, that there is no desensitization and that the blocking drug only associates with, or dissociates from, receptor channels which have been activated by agonist.

The model used allowed the scientists to estimate forward and reverse rate constants for binding of the blockers to open channels from measurements of the steady-state level of blockade and the rate of change of the current amplitude per pulse during onset and offset of blockade. As predicted by the model, the estimated reverse rate was independent of blocker concentration while the forward rate increased with concentration.