By now, you’re probably familiar with LSD (lysergic acid diethylamide). It’s the quintessential psychedelic substance alongside the active ingredient in magic mushrooms — psilocybin.

What you may not be familiar with is that there are actually dozens of analogs of LSD that have virtually identical effects.

1P-LSD is one such analog. The molecular difference is subtle, and recent research even suggests 1P-LSD is a prodrug of LSD. This means that when you take 1P-LSD, it’s converted to LSD to produce psychedelic effects.

1P-LSD is legal in Canada and held in a legal grey area in the United States.

Here’s everything you need to know about 1P-LSD.