I take pentoxyfylline (a synthetic substituted xanthine, caffeine is a natural substituted xanthine) occasionally as a nootropic and supplement for vascular hea

I take pentoxyfylline (a synthetic substituted xanthine, caffeine is a natural substituted xanthine) occasionally as a nootropic and supplement for vascular health and anecdotally for me it has several nice caffeine like properties without the jitters/ long tail, sleep effects etc. I find the listed side effects don’t happen for me besides occasional flush/blush. Which at my age is more like youthful vigor. Caffeine is is 1,3,7-trimethylxanthine, pentoxyfylline is 3,7-dimethyl-1-(5-oxohexyl)xanthine. Good effects are: sustained mental clarity, focus and energy with a smoother more stable baseline than caffeine’s bursty performance; good sleep, but strangely you can also stay up, if you prefer; feeling similar to “after exercise”. Half life is listed as under 1 hour, but beneficial effects can be felt for half a day after 400mg (a standard dose). So maybe there’s something like metabolite dynamics occurring here too. This ends my erowid/hive style “trip/nootropic” report ;)