There has been no significant research that it is harmful to your health. I have done a lot of research on dxm and have used it many times. If you don't know that much about it, please don't say how bad it is for you.
The only bad thing i found was the lesion theory. (You do pydelics and it will cause wholes in your brain.) They just disproved that a couple of years back. (It was probably government propaganda that led to the lesion theory.)
The other reason i suspected it would be harmful to you is that it was hard on your liver. I did some research and because dxm is the only ingredient (That i know of.) that uses that specific liver enzyme. There isn't any significant damage.
The other reason robotripping gets such a bad rap is because most people started of with tripple C's. These contained high dosed of acetaminophen. (Which in high doses will kill you.)
The other reason i suspected it might be bad for you is hypertension that is caused by any psychedelics. (If you have blood pressure or heart problems, then psychedelics are not for you.) I read reports of people that kept taking their vitals. It doesn't seem that the hypertension on small doses such as a 2nd-3rd plateau trip are harmful. There has been reports of using it over a long time.
The other reason i suspected it to be bad was long use and addiction. Long use has shown to cause no problems such as brain damage or anything of that matter. Addiction on the other hand is always a bad thing because thats' when the drug controls you.
The real risks i have noticed is that, for some reason makes you very truthful. So don't go out and get in trouble because you'll end up hanging yourself if you did something illegal.
I'm not saying that its completely safe to do dxm. I'm just saying that the risks are mostly myths. I'm also not saying that you won't be one of those people that get addicted to dxm. I was hooked pretty hard on dxm for over a year. Now i only do it on occasions. It's a wonderful drug and will open your mind like no other. Also ginko bilobia took about two hours before the trip sets in, makes the trip easier to remember and more intense.
Have fun and be safe and if you have any more question just shoot me a message.
Rules of thumb. Only active ingredient is dxm. Deslym sucks in my opinion because it puts me in this weird mind set but other people have enjoyed it so i'm not knocking it, it's just not for me. Gusafian will get you sick in high doses, it won't kill you but will give you horrible nausea.
Also, reading the dxm FAQ will help. Here's the link.
http://www.erowid.org/chemicals/dxm/faq/