I just read this article in the NYT called "Paramedics Share One Tip That May Save Your Life." As I read it, it occurred to me that this would be a very good idea for travelers as well. You could follow the same procedure, but keep something like this in your wallet or bag next to your phone. And of course, make sure you have your medical information on your phone. I don't know about Androids, but all of mine is in the Apple Health app, which can be accessed by medical personnel without using the phone PIN.
As a solo traveler, I wonder about what would happen if I were to be incapacitated while out walking around. And even couples and group travelers go off on their own sometimes, I would imagine. So this is definitely something I am adding to my packing/to do list.
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