Great topic, Changafarian!
Turns out my list of to-be-avoided-drugs is amazingly similair to yours, except for Cannabis & LSD.
My list of drugs to-be-avoided(in no particulair order):
1. Any and all
Amphetamines, MDMA included. Allthough I have had a period in my life
in which I enjoyed MDMA dearly and used it wrecklessly, I have renounced it, because of
it's significantly harmfull effects. The lifestyle it often leads to is one of mindless & wreckless hedonism; A sort of neurotic pleasure quest that has this undertone of profound sadness fear, escapism/denial & Animosity.
I know moderate and mindfull MDMA use exists, but it is quite rare indeed. Furthermore, MDMA is known to be quite harmfull to the brain. I like my brain.
Pretty much all other Amphetamines are about as addictive as Heroin; No drug that has such addictive potential is ever worth whatever effects it may give IMO.
2.
Cocaine: For much the same reasons I avoid Amphetamines, but then Cocaine has the added risk of making people fall into the deepest depths of Megalomania. People who use cocaine frequently soon become very aggressive, insensitive & even sociopathic people.
I am thoroughly convinced that frequent enough Cocaine use can render many people Psychopaths, literally, Psychopaths;
It seems to inflate the Ego into a monster, blunting people off to the point they are no longer capable of an inch of Empathy. I would even go as far as to say long & frequent enough Cocaine use can gradually make many of it's users criminally insane. All this comes from personal observations from people on Cocaine all around me. And there are so many.
There's probably no drug I dispise more than Cocaine, for what effects it generally has on people: It brings out the worst in them.
3.
Alcohol For much the same reasons as Cocaine: Horribly addictive, often induces
violent, harmfull behaviours. It reaks havoc on your kidney, liver and braincells.
It narrows consciousness; The opposite of what I seek in this life. Nothing about alcohol appeals to me.
4.Any and all
Opiates; Horribly addictive, physically harmfull & consciousness narrowing leading to a life of addiction, depression & apathy. As with alcohol, nothing
about this entire class of drugs appeals to me. (I once heard Opium can give one amazingly vivid, lucid dreams. Even so I can't imagine it'd be worth risking a lifetime of addiction)
5.
Deliriants like Datura/Brugmansia/Mandrake (Scopolamine & Atropine mainly I guess);
I value my (relative) sanity and my life. Enough said I suppose.
6. Pharma;
Anti-Psychotic & Anti-depressant pharmacuiticals in particulair:
From personal experience I can testify that most of these substances are much
more likely to further hurt the troubled minded than heal them. Also many of these psychiatric agents do significant harm to the body: Kidney & liver damage, jaundice, Brain Damage, severe cardiac arythmia, increased oestrogen production in men(read: Men grow boobs), extremely low bloodpressure(to the point of constantly being JUST about to faint)..etc. Psychiatrists started drugging me since I was 9 years old.
They continuously fed me every anti-psychotic & anti-depressant known to man, untill I
finally decided no microgram of this series of pharmacuitical poisons would ever enter my body again when I was 21 or so. And I have been clean & MUCH more Happy and healthy ever since.
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I won't say RCs, because I DEFENITELY see the therapeutical value of 2-CB and 2-CC,
both substances I tried. Not sure how healthy these 2 are for the body though.
It can also not be denied that LSD is an RC, but nevertheless
is LSD very therapeutically/Spiritually valuable and it's physically as good as harmless, perhaps on par with Cannabis in terms of toxicity. An LD50 exists, but is rediculously high.
That being said, there defenitely are quite a number of devastatingly toxic RCs out there.
Especially the newer ones that are appearing on the market and are innitially sold as "bath salts". I have heard very bad stories about many Research Chemicals, but the term Research Chemicals is just too broad & diverse to judge as a whole.
So I would say: Some RCs are defenitely safe & beneficial, while other RCs are best avoided if you value your physical & mental health.
PS: About your fear of LSD being impure: I thought about this too, but then wondered:
Let's say you're an immoral, greedy drug dealer that adulterate drugs to make more profits.
You might use a cheaper drug with somewhat similair properties to the 1 you're claiming to sell people, right?
Now do you know any cheap drugs that, in both terms of potency & effects, mimic LSD good enough to fool people into thinking it is LSD? I don't. I guess there are some analogues
of LSD, but they seem just as difficult & expensive to make as LSD itself.
What substance, other than LSD, is psychedelic in effect and, like LSD, is active in the range of a few 100 micrograms? No drug I can think of.
So it just wouldn't make economical sense to adulterate LSD blotters with another drug