answer:I don’t know the exact mechanics of that (I would expect grinding to a paste, mixing with water, brief boiling and then simmering for an hour with a stirrer should do it… I’d still be extra thorough and wouldn’t test it on myself), but I do know that the species common here, and those contained in smoking mixtures &c. (obviously) do not contain the cyanogenic glycosides. Are yours P. caerulea? If you only have P. caerulea, I would try using the flowers (they’ve no cyanide trap vacuoles, and I’ve heard of this usage), to either smoke or brew, but steer clear of the leaves, unless you can test your preparation… are you a chemist? If you have P. incarnata (by far the most prevalent in my locale), you’re all good, no cyanide. Sorry for the indirect answer, but I thought I’d share some relevant knowledge. My recommendation is to simply get some P. incarnata. They’re just as cool-looking as P. caerulea. Well, almost.