Drug makers spend more in marketing than R&D, and I strongly suspect that most of their marketing dollars are spent in the US. So all we're really subsidising is more marketing to doctors via our high cost health care system.
This was very apparent to me when recently on a visit in the US. There were a lot more TV commercials for different kinds of drugs than I'm used to. Ironically the required(?) list of potential side effects at the end of each ad often sounded worse than the condition the drug was supposed to treat in the first place.