A couple recent news stories came up... not directly related to this... but it had me thinking.

For example, say you have some disease for which you take medical marijuana and are forced to go into another state or country where it is illegal.

Should there be an international law that protects your ability to bring your subscription and use it... so long as it's of a resonable supply.

Or as another example... if you are going to Dubai and are on anti-depressents.  Anti-depressents are actually illegal in Dubai.

Personally I air on the side of people being able to get the medical treatments they are suggested to take no matter what country they are visiting.

That would be a pretty big order to fill, removing each country's individual choices, deciding on which medical treatments would or would not be permissable, and so on. The thing about your question though is that the issue (a global standard for allowable medical treatment ) is going to be worked on counry by country. Medical marijuana is coming, it might not be here tomorow but we're probably going to have at least some states allowing you to buy a sack wherever you like within the next 20 years. The support for straight out legalization has jumped lately....to around 50% of the population, and is very strong with the young so I can see that as the young replace the old, more and more people will be ok with it.

CNN and even fox news have shown some support for med marijuana lately, drew carrey, Arnold Schwarzzeneggar, Obama and his drug czar among others so I think that we will see a change eventually

It should factor in as something akin to diplomatic immunity (which i know is only for diplomats, but the logic for that could be twisted towards this)

though i suppose the easier thing to do is just say, if it's a choice between getting your medicine and not going somewhere, just don't go, though i suppose that sounds like discrimination (like saying to someone in a wheelchair: if you can't go to the restaurant, don't). It's a murky proposal and it would be absolutely impossible to enforce, though it has merit.

Also, isn't the phrase "err on the side?" and not "air on the side?"

No. That would cause easier drug smuggling.

If you want to make a law like that, then you either must force all prescriptions handed out to be legal in their home residence, else you open up the possibility that people would cross borders to bring back illegal goods.

If that's the angle you are going at, I don't think It would be very profitable selling weed with just enough for yourself to treat your condition. It's just not a realistic thing though, anyway.

No, it should remain up to each individual country. Sovereignty is very important.

Idealistically I would say yes, but logistically I think it would never happen.

Maybe globally is too strong a word... but I think it's something most of the nations people would want to go to could get it agred opon.

I think that's an awful idea that would get exploited the second it was allowed.

I can imagine all sorts of medical practices popping up in third world countries that prescribe cocaine and other horrible illegal drugs to people.  Then those people would go back to their home countries with essentially a free pass on those drugs. 

To make an analogy, if I have a child and I let her run around jumping on furniture and destroying things, should you let her do the same when she comes over to your house? 

The solution to the problem you're describing isn't to let one country/state override the rules of another, but to have all countries/states agree on a common set of rules.