Pseudoephedrine and Phenylephedrine… what’s the difference?

Question by : Pseudoephedrine and Phenylephedrine… what’s the difference?
I know one is regular Sudafed and the other is Sudafed PE and I know pseudo can be made into meth and so far phenyl can’t, but why? They are both ephedrine based. No I’m not a cook, just curiousity.
Good answers, but I was looking more for the differences in chemical bonds.

Best answer:

Answer by The Bulletproof Monk
I think phenylephedrine contains a compound to fight congestion that is different from psuedoephedrine in that it does not cause heart palpitations. There was a scandal over Dimetapp and other cold medicines used by children when it was found that the psuedoephedrine could increase heart rate (which is why they use it in speed). Cold medicines had to get smart or shut down, so phenylephedrine was used instead, because it does not cause heart problems. It really has no value to be used in meth, because it cannot (so far) produce the high that pseudoephedrine can. But I’m not totally sure about that.

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