Though a healthy lifestyle remains the cornerstone of good health, drugs can serve to heal, maintain healthy processes, and supply missing bodily substances. Pharmacology is the science of drugs and their interactions with the organ systems of living animals.

There are over 2,000 drugs on the market, many in multiple formulations, and that is not even counting experimental research drugs! It is nearly impossible to memorize every single drug, which is why there are computer aids and pharmacists to depend upon. However, you will need a solid knowledge base. This chapter introduces you to drug categorization by anatomical systems along with the most commonly used pharmacy drugs in these categories with their generic drug equivalents. Alternative drug products, biosimilars, and interchangeable biologic drugs will also be explained.

Many of you may find the challenges of this chapter overwhelming at first. Do not be dismayed as this is only an overview, and you will recognize many brand name drugs from personal experiences and media advertising. You can study these and other drugs in more depth as you move through your studies and career. Knowledge of common drugs will become second nature as you gain on-site experience in the community and/or hospital pharmacy.