They put in a screen to prevent clots from reaching his lungs, and they put him on a blood thinner called
Coumadin (which is the same or similar to warfarin, I believe). He will probably be on the
Coumadin the rest of his life. That's standard procedure, as I understand it.
I take Evista (raloxifene) to fight osteoporosis. The box says that it could cause blood clots, so I know it's possible for drugs to be the culprit.