From an ethical point of view: a solid yes
Is there a chance that freely available information about drugs will increase the damage drugs do to society? I have known and still know drug users from teen-aged to 40+, as well as kids who had access to drugs but chose not to do them. My impression is:
- such information won't lead to non-users becoming users. Drugs are not an "out of sight, out of mind" matter, they are very much in sight. And keeping them a mysterious taboo actually increases their allure. On the other hand, discussion like "There is also evidence that 6-MAM binds to a subtype of μ-opioid receptors that are also activated by the morphine metabolite morphine-6β-glucuronide but not morphine itself" doesn't produce a yearning to try a drug, it brings it from the realm of cool dudes doing forbidden things to the realm of boring eggheads.
- such information will have neutral or slightly positive effect on the number of users kicking the habit I don't see how good information about the medical side of illegal drug use can prevent somebody from stopping. In fact, somebody wishing to stop needs strong social support, and if somebody in this position finds on this site a place where he is heard and taken seriously, this will be one more small prop of the hundreds he needs to get back on track.
- such information will have slightly positive effect on drug users Educated drug users are more likely to use their drug in a safe way, avoiding overdose and comorbidities. Thus harm to this particular part of society is reduced when there is more information about less harmful drug practices. If you are worried about this tricking non-users into thinking that doing drugs is safe overall: Everybody I know can discriminate the danger of overdose from the danger of addiction, even in early puberty. I've never heard somebody say "well, if this is a safe way to take it, I'll try".
So having more good quality information easily available will likely neither increase the number of drug users, nor increase the amount of damage drugs are doing to their existing users. It could even have the opposite effect.
From a cultural point of view: a more cautious yes
I dislike the generalized censoring of information, turning certain subjects taboo or even illegal. But we humans can, and should, hold back discussion of certain topics under certain circumstances, out of consideration for others for example. So the question is, is this discussion appropriate for a Stack Exchange site?
For my personal understanding, and in the culture of the social circles I move, a levelheaded discussion on drugs from a medical point of view is appropriate for most settings, including a professional one. I opened the drug-related question today from my work computer and did not think anything of it.
But cultures are different, and sometimes, it can be a big deal. The network has had incidents before due to controversial topics making it into the list of hot questions, even back when the list was hidden in the notorious multicollider. Among the objective arguments brought up in one such situation by Jeff Atwood was that this content, once it appears on Stack Overflow, risks the site being automatically put onto the nanny list of corporate filters, so that a discussion on English could have deprived thousands of programmers of SO help and also seriously hurt the SERP placement of the whole network. In another case, users were very upset by a question about marijuana butter on Cooking.
Regardless of how open the Health users are towards questions about illegal drugs, whenever they are mentioned in the title, they will probably have enough magnetism to get the most views (drugs are a subject on which everybody has an opinion) and will probably jump onto the hot question list, leading to the lamented effect plaguing some SE sites: "our worst questions get on the hot list".
I would still like to see legitimate medical questions about illegal drugs included, because they are very much part of human health and disease. But if we don't like the potential cross-community effect, we might try to think of preventive strategies, maybe extensive editing of the titles to sound as neutral as possible.