Can a pharmacy be penalized for giving out a wrong prescription?

My father has been using the same pharmacy for at least 5 years and had gotten a new prescription about a year and a half ago to help him with his blood sugar since he's diabetic. He had to get the pills since he is overweight and has high blood sugar and needed them to lower it. Well my dad isn't in perfect health other than that, he had Guillain Barre Syndrome in the past and now he's having post-Guillain Barre, which is basically the same symptoms of post-polio. Well anyway, he had been taking those pills for a year and a half and that pharmacy had been getting crappier and crappier. Finally, my mom decided to switch pharmacies yesterday (they're both the same company, just different locations) and they found out that the other locations' pharmacy had been giving my father the wrong pills. There are two different strengths of the same pill and my dad had been given the stronger pills and had been taking them for OVER A YEAR. While on the pills my dad experienced double vision and a lot of times he would get so tired that he had to fall asleep many times throughout the day..now we know it's because of the pills. They had been so strong that they dropped his blood sugar every day so drastically that he just basically ped out. My father talked to a lawyer and they said there's nothing they can do, but isn't there something that we can do to make them realize that they could have killed my father for giving him the wrong medication?