So I recently purchased cyproheptadine from an online pharmacy, I took half a pill 2mg at 1pm no effect 3 hours in decided to take another 2mg, still nothing, then I took another full pill 4mg around 2 hours later, no effect whatsoever, am I immune to the drug or something the way it is noted on this forum is it should knock me out as its a strong sedative? The only thing I can think is the expiry date on the box says 11/2018, could this be the issue, as I'm pretty disappointed with the high expectations I had for cyproheptadine, any ideas? Brand is Periactin by Auden Mckenzie