That's true. However there are a wide variety of phenethylamines that are truly beautiful and useful psychedelics. The ones that mainly come to mind are 2C-E, 2C-T-2, DOC and mescaline. Each of these is special and deep and beautiful and totally worth exploring. However I do agree in general that tryptamines seem much safer.
That said, the NBOMe drugs do fit the profile of hERG channel blockers, which cause long QT syndrome in susceptible individuals - a condition that can cause your heart to stop beating suddenly. I have a feeling that's the causative factor behind many of the mysterious deaths of otherwise healthy users in their mid 20's taking 25x-NBOMe and suddenly dropping dead.
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