Is Medical Marijuana ethical?

Is Medical Marijuana ethical is the question. The real issue is should we make a now illegal drug, such as marijuana legal for Medical use. Opiates are legal in the form of Medical use, yet the original form is illegal. So what is the difference, not to mention that Marijuana is ten times safer then Opiates. If we were in any other country this topic would not be as big. Just look at Amsterdam, Marijuana is complete legal and is classified as a "soft drug". According to Amsterdam.info, Marijuana is regulated to no more than a 5 gram transaction and it is not sold to minors. If Marijuana is completely legal or decriminalized in other countries then why is it so farfetched to just legalize Marijuana for medical purposes only? How is it unethical to legalize Medical Marijuana when 18 of our states already have in some form legalized it on a state level? Also some of these states have approved Medical Marijuana use for many years now, so what is holding up the rest of our country. We should not completely model what would be our own system for legalized marijuana off of Amsterdam, but we should use Amsterdam as an example and find out their statistics before and after legalizing marijuana, and if they use it for Medical purposes, then what are their methods.

 Skelton, Peter. "Amsterdam drugs." http://www.amsterdam.info/drugs/. Amsterdam.info, 25 Jun 2013. Web. 25 Jun 2013. <http://www.amsterdam.info/drugs/>.