The most dangerous thing in Absinth would be alcohol (percentage of modern Absinth is about 70 %. In nineteenth century it could be about 90%, but they drank it mixed with water). The second famous content of Absinth is thujon - that is supposedly the substance that makes you see Green Fairies
. But it was never made clear if it is really so.
Soldiers of Napoleonic armies first drank absinth to avoid infections, and they brouhgt the habit back home. It was the favourite drink of decadent writers and poets and the likes of Aleister Crowley.
If you never tried it, prepare for a very bitter taste. You probably won't like it.
But the more you drink, the better it tastes.
My advice> If you really want to drink it, do it slowly and drink some water too. If you don't like the taste, it is OK to add a sugar cube into it.
Whether it sorts the men from boys, I don't know. But you can have a lot of fun offering it to your unsuspecting friends.