Pharmacists dispense drugs prescribed by physicians and other health practitioners and provide information to patients about medications and their use. They advise physicians and other health practitioners on the selection, dosages, interactions, and side effects of medications. Pharmacists must understand the use; clinical effects; and composition of drugs, including their chemical, biological, and physical properties. Compounding--the actual mixing of ingredients to form powders, tablets, capsules, ointments, and solutions--is only a small part of a pharmacist's practice, because pharmaceutical companies in a standard dosage and drug delivery form produce most medicines. …