This is an interesting thread with a quiet long history of just over a decade.
To begin with fairnymph writing about the two optical isomers of ketamine and going onto TheTripDoctor whom surely is an expert in a different chemical substance, though is also correct when concerning the effect of the different stereoisomers of ketamine.
There was problems in using racemic ketamine in medicine due to its psychoactive properties, the properties that I suppose are more favorable to yourself. Well what's positive for one person can turn out negative for another. Anyway, when it was possible to produce the S-ketamine, it was more favorable molecule than the R isomer, because it not only was more potent for the NMDA receptor than R-ketamine it did not have the psychoactive properties to such an extent as the R isomer.
Theoretically the R-ketamine is the one you ought to be more interested in psychedelically, however this has not entirely have to be true, because a mixture of both ismoers can favor the psychoactive effect when in an optimum ratio. This is a theory for I do not know what role does the NMDA receptor play, whether the biding of it can favor a greater psychedelic experience.
One good example of the point I am trying to make concerns amphetamine. The two isomers that is the l (R) and d (S) of the simple form of amphetamine molecule the 1-phenylpropan-2-amine. One of the isomers the S is better at stimulating dopamine release, however it is the R isomer that stimulates the release of norepinephrine several times more than the S isomer, though it has a bad effect on the heart. The conclusion is that a 25% S and 75% R mixture would produce a quiet stimulated effect with a touch of euphoria, on the other hand a 25% R and 75% S mixture would produce a rather euphoric effect with a less stimulated effect than the first version mixture. Then again you can go for a racemic compromise and go 50:50.
Anyway this post concerns ketamine and one thing that I can say about ketamine overall is that it is a truly promising chemical substance with a huge potential in medicine and aiding in solving many problems sometimes not even medical in nature.
The other substance that has an extreme potential in medicine is LSD. I know this thread concerns ketamine, but this has to be pointed out somewhere. At present in psychiatry their really aren't any chemical substances that cure psychiatric disorders, they all merely are aimed at eliminating the side effects of the disorders, however by using painkillers to eliminate pain you don't eliminate the source of the pain that is the problem.
LSD has been demonized I predict mainly to fuel the psychiatric-drug-production-money-making-machine and their have been lies written concerning LSD. For example I have read in a pharmacological dictionary that LSD is a toxic substance or that it aided the production of toxic substances in the body (I am not sure of the words used), in whichever case that is not true, for LSD is a a relatively non-toxic substance. The only documented studies concerning LSD and the damage it can do to the human body concerns the ability to cause mutations in chromosomal DNA of certain cells. I have read these various studies done both in vitro and in vivo and to conclude based on those studies, that if LSD has any effect to cause mutation to chromosomal DNA of certain cells it is equivalent to the damage caffeine can do. In other words, by drinking coffee you will damage your chromosomal DNA of certain types of cells pretty much to the same extent as if you would when you consume LSD, in general.
The other lie concerning LSD in that pharmacological dictionary is that most medical experts came to the conclusion that LSD has no potential in medicine. This is the biggest lie of them all. What is safer to use in psychiatry, psychotropic medication (drug used in psychiatry) or LSD? I know of a case of a person whom abused a certain psychotropic medication for three days in a row and that person never came back to be whom he is. There have been made irreversible changes in his brain and that person lives in an alien reality. This is the potential of psychotropic medication. They are very powerful and dangerous substances that if misused can be lethal, but it is LSD that is demonized to be the dangerous molecule. This is ridiculous to the power of infinity. LSD is extremely compatible with the human body and does alter the state of mind of the person, however when the substance is out of the body to much extent you return to "normal". You are not exactly the same person as before, because you already have experience you did not have, but you don't exist in the altered reality after the LSD experience.
LSD has enormous potential in psychiatry to in fact treat psychiatric disorders and not just patch them up by eliminating the side effects of psychiatric diseases. Of course there are psychiatric disorders that are more difficult to cure, due to actual physical changes to the brain, but that is a different story. All that needs to be done is intensive research in the potential ways LSD can be used to treat specific disorders and with the aid of ketamine and other chemical substance, things that first seemed impossible, can become possible, for for every problem there is a solution, you just need to find it and then act. Psychiatrists in general do not even understand sufficiently the many disorders they try to treat, for if they understood them, then surely they would know the solution to them, but as you don't understand the problem, the same you can't solve it. I know that LSD is the miracle molecule in psychiatry, but who will listen? I guess a man has to take things in his own hands and begin the research to prove the point. So be it.
Take care to all
שלום
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