Law suits don't exist without fault. Negligence case against pharmacists are so rare as to be minimal. They no longer compound drug, they merely dispense drugs made into pills, and bottles of liquid. Their major fault has become the young women pharmacists just out of school who have not the slightest idea of how to relate to people or treat customers. Many of them think they're in the business of second guessing physicians.
A few do. It's often required for veterinary prescriptions, where the dosage is smaller than anything available in the "human" pills or capsules.