Is a dissociative like Ketamine and PCP. Make sure your source contains Dextromethorphan and nothing else such as Max. Strength Robotussin. If it has only DXM than occassional use is relatively safe. How strong your trip will be depends on how much robo you chug, try from 2/3rds to a full 4oz bottle for your first time and have a trip sitter present. Marijuana makes the experience a hell of a lot stronger.

I personally don't like DXM because I only feel good for about half an hour before I get nauseaous and then just feel 'dead' for 2 hours. After that its okay, a bit hard to comprehend stuff though. The day after you'll feel out of it, which goes go with a bowl. Some people really like it, so I guess it doesn't hurt to try.