Greta wrote: ↑May 15th, 2018, 5:25 pm
I made it clearly in the post you snipped. It was a personal example to help illustrate just how much individual biochemistry can vary. One person's meat is another's poison is not just hyperbole, it's a literal fact.
It is true that every human being has his/her own unique biochemistry; and it is true that because of this there can be substantial differences in the way that different individuals react to a given dose of a particular drug.
There are, for instance, a
significant (i.e. non-trivial) number of individuals for whom the administration of ,say, morphine, will generate pronounced emetic effects.
Generally speaking, the higher the total bolus dose of morphine administered, and the more rapidly- acting the dosage form, the more likely a subject is to experience acute emetic side effects.
Morphine is prescribed for analgesia in the case of patients who are suffering from acute or chronic pain. If an average, common or garden variety adult, Joe Citizen, is in pain because he has just broken his leg in multiple places in a car accident, a standard dose of, say, one to two 10 mg morphine tablets every four hours will relieve most , if not all, of his pain without causing any nausea or vomiting.
However, as you say, there are a
minority of individuals who happen to be
particularly sensitive to morphine's emetic properties, such that even a relatively low orally administered dose of the drug like this will quickly induce severe nausea and/or vomiting.
Also, as I say, when a
relatively high dose of an opiate drug is given to Joe Citizen in the form of a
rapidly acting dosage form, he will very likely vomit shortly after. For example, if I inject Joe Citizen with say,50 mg of pure heroin ( diacetylmorphine) intravenously, he will probably throw up quite promptly after the injection has been administered. Equally, if you ask any "junkie" about shooting up heroin, they will tell you that when they inject street heroin that is relatively pure (highly concentrated)) intravenously, it will often cause them to vomit ( they say it is the most painless kind of vomiting that you could ever imagine). I remember, for instance, in the 1980s, the pavements outside the pubs and clubs on Oxford Street ( you're from Sydney, right Greta, so you know Oxford Street?) being awash with vomit from injecting heroin addicts every Saturday night.
What do you propose the psychiatric profession ought do with respect to the fact that the official guidelines they have developed for the prescription , by psychiatrists, of psychoactive drugs ( which are indeed based on "utilitarian averaging" as you put it) do not take account that sub-set of individuals who will respond to a given drug in an atypical manner? On the one hand, it is imperative ( for legal and many other reasons) that some kind of firm, official dosage guidelines are set by the profession's regulating authority, in particular for the prescription of addictive substances like morphine and dexamphetamine, on the other, there seems to be no avoiding the need to base official advice about safe dosage on past experience of how the MAJORITY of average adult subjects respond?
If you are suggesting that lay members of the public should be at liberty to lawfully access and self-prescribe whatever doses of whatever type of psychoactive drug they feel are suitable - in their opinion - for their own individual needs (recreational or therapeutic); that is, that all psychoactive substances ought be legalised for public use, I do not agree.