You may have seen abbreviations on prescriptions such as q.i.d. or b.i.d. and wondered what that meant. These and other instructions are written in abbreviations for Latin phrases. Centuries ago, all prescriptions were written in Latin. Now, only the directions for taking the drug have kept that trait. For the average person with no medical background, they don’t mean anything. While your pharmacy should interpret those for you, mistakes can happen. The better you understand the directions, the more protected you are from a potentially dangerous error.