Basic Principles of Pharmacokinetics



As Lead Emergency Department Clinical Pharmacist at Sharp Memorial Hospital in San Diego, California, Dr. Ashkan Khabazian collaborates with physicians and other staff to treat trauma and other acute conditions. Dr. Ashkan Khabazian applies principles of pharmacokinetics to ensure that each patient receives the correct drug dosage for his or her body.

While it is important for a pharmacist to understand what the drug does to a body, it is equally crucial that he or she understand how the body processes the drug. This area of knowledge is known as pharmacokinetics. It gives pharmacists a framework through which to understand the pathways the drug follows through metabolism and excretion.

Pharmacokinetics helps identify how a drug reaches a site in the body, how much of a drug reaches the site, and in what tissues the drug is likely to concentrate. This knowledge allows a pharmacist to develop dosage plans based on an individual patient’s concentration of tissue types and how this will affect the drug’s movement through the body.

Pharmacokinetics also allows pharmacists to analyze a drug’s metabolism by the body and to predict how certain substances in the patient’s system might affect this process. Pharmacists will also consider how the patient’s age, genetic makeup, and organ functions might change the rate at which a drug breaks down, which in turn impacts the drug’s effectiveness. Such a knowledge of the interaction between drug and body helps the pharmacist to more effectively administer drugs, which may in turn improve patient outcome.