Actually the last time I got my prescription, I had to be informed by the pharmacist that my medical records are private. I also had to sign a book that acknowledged that they told me about this law. And the reason for that rigamarole is that your pharmacist rats you out preemptively. Law enforcement KNOWS you have prescritions, and KNOWS exactly where to look for them - in a database they already have. Calling that "privacy" is a lie.
A lot of people on this Web site seems to be pretty paranoid about law enforcement for some odd reason.