From my reading it appears that drugs like marijuana and opium were well known and documented throughout Antiquity but do we have any evidence of strictly recreational use during the ancient/medieval period, or were the use of these drugs strictly reserved for religious or medicinal purposes? I vaguely remember HBO's Rome series depicting Cleopatra with a drug problem. Would something like this have been common in the ancient or medieval world or is drug addiction as a widespread societal problem a relatively recent phenomenon?
Assuming that you're comfortable counting the Scythians and aren't just interested in Greece and Rome...
Hemp is native to the Central Asian Plains and Adrienne Mayor's book The Amazons has a really interesting chapter (Chapter 9) on drug use among the nomadic cultures (there's more than one; Scythian is sort of a fuzzy term) of that region to whom she attributes a lot of Greek understanding of, well, warrior women among the ancient horse peoples of the Eurasian Steppe.
She specifically says that cannabis was valuable for spiritual and recreational purposes. Her references for this claim include:
According to Mayor (and I have no reason to doubt her), Herodotus discusses cannabis use among the Scythian tribes he is familiar with, and the translation I've got in front of me gives no indication that it's intended for a particularly ritual or religious purpose: Herodotus compares inhaling cannabis smoke in large gatherings to the Greek use of wine as an intoxicant.
The Scythians that Herodotus reports on also apparently used cannabis "seeds" (buds, actually, but the difference isn't always obvious to a non-user) when partaking in steam baths.
In terms of material evidence, there were also apparently hemp-burning kits found in the graves of Pazyryk culture men and women in the Altai region. These hemp kits were mixed in with other regular daily tools (i.e. not obviously ritual items), so Mayor says that "the archaeologists conclude that cannabis inhalation was not restricted to ritual use but was part of everyday Scythian life."
Hope this helps!
This is a good question. I can't comment on the Medieval period but widespread drug abuse was not really a thing in antiquity (unless you count alcoholism).
This was because most drugs were hard to obtain and expensive. Even once they were obtained, dealing with wild plants or fungi using ancient methods of preparing and administering them meant the amounts and concentrations were wildly imprecise.
It simply was not feasible for the average person to get high recreationally. Because of this, the ancient Mediterranean never really developed a drug culture in which knowledge of various drugs or how to obtain and consume them would become common.
Ancient authors do not really wrote about drug addiction as a societal issue because it was probably effectively non existent.
Cleopatra's opium addiction in HBO's Rome was added by the showrunners for drama, although historically some Roman propaganda did accuse her of excessive drinking.
Still, it may have been possible for the wealthy to get high and that this could become an addiction. It has been suggested that Marcus Aurelius' consumption of opium leaves may have become an addiction.
This answer goes into greater depth but mostly focuses on the Roman Empire: