Anesthetic Hallucinogens

Residual Effects of MDMA Anticholinergic Hallucinogens Dissociative Anesthetic Hallucinogens... 

Phencyclidine (PCP) and ketamine are classified as dissociative anesthetic hallucinogens. They produce a potent intoxication at moderate doses and complete surgical anesthesia at higher doses. Violent psychotic reactions appear to be fairly common with PCP. 

For many years it was believed that the brain mechanisms underlying the effects of psychedelic hallucinogens and dissociative anesthetics were separate and distinct. Indeed, there has been considerable debate about which represents the best drag model of schizophrenia. However, recent data show that the two classes of psychotomimetic drags share a common final pathway involving an increase in the release of the excitatory neurotransmitter glutamate. 

Phencyclidine (PCP), one of the arylcyclohexylamines. was developed and originally used as a general anesthetic for humans. Due to psychotic and hallucinogenic reactions, use of the drug for humans was discontinued. It is now used legally only in veterinary medicine as an animal immobilizing agent. 

Although this drug is categorized as a local anesthetic, I have chosen to put it in with the hallucinogens because of the psychotomimetic effects that it produces. Cocaine is not a phenylethyl-amine, but it produces central nervous system arousal or stimulant effects which closely resemble those of the amphetamines, the methylenedioxyamphetamines in particular. This is due to the inhibition by cocaine of re-uptake of the norepinephrine released by the adrenergic nerve terminals, leading to an enhanced adrenergic stimulation of norepinephrine receptors. The increased... 

The answer is E. Anesthetics are highly lipid-soluble and experiments with isolated membranes indicate that these molecules can dissolve in the hydrophobic center of the membrane bilayer. This causes a measurable increase in the membrane fluidity by disrupting the packed structure of phospholipids tails. This is considered to be the main, direct mechanism by which this class of drugs inhibits neurotransmission (pain sensations) in neurons. Hallucinogens and opiates may also affect membrane fluidity, but their effects occur by indirect mechanisms, resulting from changes in the protein or lipid composition of the membranes. 

Many drugs currently on the market are racemic mixtures. Ketamine, for example, is a potent anesthetic agent but its use is limited because it is hallucinogenic (making it a drug of abuse widely known as "K ). The (5) isomer is responsible for the anesthetic effects, and the (/ ) isomer causes the hallucinogenic effects. 

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