It has been some years since my wife's prescription was misfilled. The last time, I wrote a strong letter of complaint to Walgreens in Deerfield, IL, and they replied. I believe I filed the letter in my stuff somewhere.
In any case, others have had their prescriptions misfilled too. I believe the following link explains:
My wife has 40% apparently permanent kidney damage, very likely as a result of misfilled prescriptions. [We caught it 3 times, but we may have missed it several other times.]
She no longer takes that drug, and we get other drugs elsewhere.
It would be convenient to forgive and forget, as proving Walgreens was a fault might be hard. But, the damage is done and is irreversible. Looks like my wife has to take medication for hypertension for the rest of her life.