Unfortunately, we are not able to be certain about the quality of the drug we are taking. We buy from the Silk Road (well, Agora now I guess - still waiting for things to calm down), where we read reviews and base our decisions on the gossip posted by other users.

Something about our current batch seems off, everyone's been having weird trips. Despite this red flag, we've taken over 2/3 of the batch. You can't be 100% certain doing testing-at-home either, because there are inert compounds that will test positive for LSD - a careful dealer can fake the test results.

And it's a damn shame, because if you are uncertain about the quality of your substance, those doubts will amplify throughout your trip (that is the nature of psychedelics), and every little effect that you aren't expecting will cause a flurry of uncertainty.