Actually that's what I thought was on the sugar cube too, but IIRC the military abandoned LSD as a truth serum in the mid to late 60's as it was pretty unreliable with it's hallucination producing effects. It is quite possible that the Dharmites still used it as a primitive truth serum.I was blown away by the scene with Sayid telling the truth about everything. I did not pick up on this, and perhaps it was pretty obvious to most people, but my Dad told me he was given LSD, which in the 70s, before it was a recreational drug, was used as a truth serum. He said they used to put it on sugar cubes, like the one they gave Sayid.