When I saw these board postings on medical mistakes, one experience of mine came to mind.

A short time ago, I was out of town and had what turned out to be a kidney infection with kidney stones.  I went to one of these open-late-at-nite-and-Saturdays immediate care offices.  When I got out, the doctor gave me a prescription chit.  I went to one drug store, and they said that they did not have that medication in that dosage, told me mto try somewhere else, and gave me the chit back.  I went to 3 other drug stores (all major chains), with similar results.  I then went to still another drug store (this one an independent); they told me that the doctor had written down the wrong dosage.  He said that the medicine that was prescribed came in 200mg and 400mg sizes; the doctor had written down 300mg.  The druggist called the doctor to ask about this.  She told him that 400mg was OK, so I got the 400mg pills.

Not sure why the other druggists did not catch this.

IMO the major chain drug stores didn’t want to get involved.  It was easier just to tell you they didn’t have it in stock.

When they have stores all over the U.S. there are different state laws regarding how they  prescribe.  Corporate Headquarters instruct the chains to take the path of least resistence.