Another word to the wise regarding this drug:
Do not snort pseudoephedrine!

I can tell you, from personal experience, (hey weren't we all 16 once?) that if you try snorting this drug, it WILL feel like you've just jammed a freshly made batch of plaster up your nostril. It will sit there and harden, and the rest will drip down the back of your throat. Personally, I vomitted profusely at that point, when the dripping began, but then I'd been drinking plastic-bottle vodka all night and chain-smoking clove cigarettes. Neither of which I advise doing, as well. And yes, you will develop a tolerance to pseudoephedrine, whether you swallow or snort it, and you will need to do more at some point. The addiction is much like a cocaine addiction, in that the addicted may swear up and down they're not addicted (even though they'd sell their record collection for more, er...or so I've read), despite the fact that there is a definate withdrawal you go through. It's not quite as nasty as heroin withdrawal, but it's no walk in the park, either.

Bottom line - use this drug for its' intended purposes, such as to treat asthma, and stick to the real drugs if you want to get high; they're much more expensive, and if you're a poor student like I was, it's neigh impossible to afford a seriously debilitating coke habit, while it' s dangerously easy to develop a pseudoephedrine habit (it's available in 24-hour supermarkets!). Not that I'm condoning cocaine addiction...but I think you get the gist of what I'm saying.