Walgreens pharmacy, do you know anyone who has ever been given the wrong medication.?

Walgreens pharmacy, Columbia, South Carolina gave my wife double the amount of the prescription called in to walgreens of a chemotherapy drug called 6-mp mercaptopurine. This is a deadly drug and given my wifes height and weight this dosage was way to much for her body to handle. She now has liver damage resulting from the drug and Walgreens is pretending this never even happened. Looking for any other people out there who have had a problem with walgreens pharmacy and drug mixups and errors.