Just one more note of support - I am somewhat familiar with the laws about professionals and confidentiality: these laws and codes were in place before HIPAA ever appeared.

Yes: a health professional has no right to expose any information about you to any other person without your written consent. The comments in the store in front of others fall into this category. The conversation with the relative goes a lot farther. But I THINK it's even illegal for him to shout, "Miss Smith -- your aspirin order is ready!!" where others can hear it. Though I would not make a case of that one myself.

In your position I would tell him off unless you put yourself in a bad spot by doing so, and I'd make a complaint about him to the pharmacists' licensing organizataion. This is enough to scare him and prevent his doing this to you or other people. I believe he'd be notified of the complaint and reprimanded, at the least; and a file would be opened or added to.