Jogging on Santa Monica’s beach, a traveler twisted his ankle. He went to a clinic where an X-ray revealed no fracture.
That was two days ago, he informed me, and the ankle was healing. He was to fly home tomorrow, and his doctor in Switzerland had suggested he get an injection to prevent a blood clot. I receive a sprinkling of these requests, all from foreign travelers. They began a few years ago when the media began reporting clots in travelers after long plane flights. The risk in healthy people is tiny but not zero and concentrated among those who fly more than four hours.
Drugs to thin the blood such as Coumadin and heparin have been around for decades but are too dangerous for healthy people. In 1993, the FDA approved Lovenox, a refined form of heparin, safe enough for use outside a hospital. My wife gave me six weeks of daily injections after I broke my leg in 2003. It was still under patent and wildly expensive, but generics have appeared, so it may soon become fashionable to get a shot before a long flight.
So far no Americans have mentioned the subject, and I give foreigners the traditional advice: walk around and drink plenty of fluids. Techniques that don’t work include compression stockings (unless fitted by a professional they may make things worse) and taking aspirin. Aspirin prevents clots in arteries, but clots from immobility occur in veins.