Nitro:

The TV show I watched was quite interesting. Evidently for many years the stuff was banned in many countries and the USA. In fact, I think it still is in the USA?

According to the show, some of the reputation for hallucinations and the "myth" surrounding the drink was due to its meteoric rise in popularity, particularly in France in the late 19th century. As with many such market occurences, this popularity spurred the mass production of cheap, low-end "absinthe", or actually copies thereof as many distillers tried to get a piece of the growing pie.

Some of these cheap imitations contained arsenic and other toxic chemicals added as coloring agents and were in fact quite dangerous to drink. Recipes of even the legitimate makers were typically considered trade secrets and jealously protected, and this "secrecy" trumped production standards surrounding the drink. In other words, since the recipes were "secret", it was difficult to establish quality standards and any old basement bandit booze bottler could churn out any ole licorice-flavored, funky green, methanol-based, lamp oil and call it "absinthe". Things got so bad that the drink itself became synonymous with antisocial behavior; violence, crime, Rump-Ranging & Butt-Bashing, Bank robbing and the like. This, just at a time when anti-alcohol Prohibition movements were gathering steam. Indeed, the toxic absinthe knockoffs helped fuel that fire.

According to the show, properly-made absinthe is in essence {no pun intended...} no more or less hazardous to drink than...whiskey or rum or brandy... Of course, all spirits have their downside to be sure!!

We have to remember that before the Industrial Revolution, spirit-making was relatively inefficient, time-consuming and expensive. With the advent of the IR and economies of scale, spirits became cheaper and more available particularly to the urban masses and served as self-medication at a time when painkillers, etc were rare indeed {particularly in the new urban living that separated many people from traditional, natural meds}. And of course, freewheel drinkin-it-like water spirit-sucking is without a doubt a bad thing for all involved.

I am no tetotaller but I do thank the Prohibition and many church movements for a few things in that regard, one of which was assistance in building a culture of moderation involving drink.

Late-19th century "absinthe" was, evidently, something of a catchall term for drinks that led to really destructive behavior.