Smoking is a cause a lung cancer. GHB is a cause of sleep raep
Side-note on poisons and rape drugs: there're tons of horrible poisons and venoms too easy to make and impossible to forbid, so enforcing control on drug just because it can be used to poison one's food and drink is idiocy.
Rape drugs are quite a different thing: they're potent sedative substations which can knock out your victim without killing her/him, but warping out her/his memory. After "spiking" some girl's drink, you can bone her drooling body and she will be unable to remember WTF just happened next morning. In most cases, rapist will use either some potent benzo (flunitrazepam being the most infamous) or some butyrate (usually GHB).
It should be clear that if you deny people of drug which are easy to OD when used perorally, then to-be killers will just switch to anything else toxic. Denying people of date rape drugs should, in theory, either make "drink spiking" a very rare practice or even completely end it.
However, despite The Man throwing substation restrictions left and right, the date rape is still a common thing (sad but true). Why? For a multiple reasons.
The first is that one of the most common "date rape drugs" is alchohol. Yep, just a booze without any spike. Quite a large dose of it is required, so the rapist needs to be creative or just force-feed his victim. Outlawing alchohol is extremely dumb idea in 9 out of 10 cases, and it is impossible to actually do it outside of totalitarian shitholes like Saudi Arabia, so moving to the next point.
The second is that chlorophorm - classic rape drug - can be made at home from bleaching powder (HWO I MAEK HLOROFURM?????)
The third is that benzos and other sedatives, while strictly controlled (in civilized countries), are still far too common to be that hard to obtain. They are extremely fucking useful and thus fabricated en masse, so of course criminals are able to get some.
The fourth is that it is 21th century now. You can order potent designer benzos (yep, shit like this exist) from China and rape anything that moves. Trying to prevent it usually results in a complete clusterfuck: mail ordering becomes overpriced, you have your mail later than you should and The Man violates your privacy by scanning, sniffing, reading and cracking open random (or even all of the) orders. And date raping will go on anyway since weird mail-ordered drugs are only a tiny part of rape drugs market: designer sedatives usually (ab)used by orderer him/her self and not usd for rape anyway.
Outlawing all of the so-called "rape drugs" is just impossible. While it may be wise to put some kind of control on them (and to continue ongoing switch from benzos to less harmful and addictive sleep-aid pills), just forbidding them is an idiocy. Stay calm and cook chlorophorm