> Isn't that one of the ingredients in meth? Not an ingredient -- a precursor. Methamphetamine, pseudoephedrine and and phenylephrine are very closely related:

> Isn't that one of the ingredients in meth? Not an ingredient -- a precursor. Methamphetamine, pseudoephedrine and and phenylephrine are very closely related: https://cen.acs.org/content/dam/cen/83/13/8313govpol1imgs.gif https://cen.acs.org/content/dam/cen/83/13/8313govpol1imgs.gi... To convert pseudoephedrine to meth you have to remove a hydroxyl (-OH) group in a way that leaves the resulting molecule in a specific isomer. Doing this at high yield is challenging, but it turns out that if you're willing to live with lots of horrible impurities, you can do it in a cola bottle. PE has the same structure as pseudoephedrine, but in a different isomer, so it cannot be converted with the simple approaches. Unfortunately, PE is also useless for decongestion, because -- surprise! -- the isomer matters a lot for effectiveness.