what would your advice be to a European traveling to the US? I think it would be just as difficult.
i'd like to think the for-profit labs would be happy to take money to provide the service, provided they could verify the need for the labs. worst case, you could visit an urgent care facility or emergency room and (have most of them, anyway) do the labs in-house or with a contractor that would take the vials elsewhere for processing. i wouldn't choose an ER (or, as the UK would say, an A&E) as my first choice, mostly because of exorbitant costs. in an emergency, though, one does what one must. if you came to the pacific northwest, dynacorp/labcorp can be found all around the puget sound/seattle area, frequently inside health clinics and hospitals.
fwiw, i'm not searching for drugs, or even medications for my problem. i'm looking for someone competent to stick a needle into a vein, draw "enough" blood to test, then provide the resulting value to me. the draw itself takes 30-40 seconds, and the labwork a few hours max. with the result, i can take it the rest of the way. seeing a foreign doctor for them to re-diagnose me just to write a permission slip to draw blood might take months to years, especially if they don't personally have that expertise. oh, and i'd need numerous expensive blood draws just for that. the irony... :)
it almost sounds like the easiest way to "fix" this is have my oncologist/hematologist write a 90-day script for something that provides a similar result (anticoagulation), but does not require the testing. for me, the risk is not small -- those drugs may do similar things, but they act differently and can cause their own issues. but, as long as my trip is less than 2-3 months, it might be worth that risk.
thank you, everyone, for a fascinating conversation. i hope to return to the states by mid-spring with notes about how it went, what i found... :)