Even though it is usually taken in the form of Robitussin, DXM's incredible powers shouldn't be underestimated. There are ways of extracting it, and I don't think I've ever had a bad trip on it.
Oh, and Gondie, you might want to do a bit more research. There have been no long term health concerns that have been attributable to DXM. Olney's lesions are the usual concern, but it has been found that Olney's findings were wrongs. Diarrhea and rashes are INCREDIBLY rare, but nausea is something to count on. If you do mushrooms regularly, though, it's nowhere near as bad as shroom sickness. Panic attacks and depression can happen with any hallucinogen.
Oh, and the blood rising in your brain bit is an overplayed urban legend. Lightheadedness can happen, but it's no sign of something as serious as that
Also, only a very small margin of people are naive enough to become addicted to DXM. It's easy to love, but it's very hard to be ballsy enough to abuse. VERY HARD.
The only ill effects I've experienced are hangovers, which as Gondie said can be really harsh. It's not as bad as say, a coke comedown, but it can get to you. It's like having a slight headache while your body is mush.