You might think this is a simple question, especially for an expert in pharmacokinetics. Well, this question is full of controversy with each scientist having their own opinion. I think this is because the definition of pharmacokinetics is simple, yet pharmacokinetics science is broad in scope.
The word pharmacokinetics is from two greek words (see wikipedia for more):
kineticos: to do with motion
Simply put, pharmacokinetics is a study of the movement of drug in the body.
Drugs are are like apple pie
Think about eating a slice of apple pie. After you put the scrumptious food in your mouth, it travels to your stomach and eventually to your intestines. Then your body begins to absorb the nutrients in the pie. Following the absorption process, the body distributes the nutrients to different tissues (eg muscles, brain, lungs, etc.). Once at the tissue, the body converts the nutrients into energy, adipose tissue, etc. Finally, any leftover chemicals are eliminated from the body in the urine or the feces.
Pharmacokinetics and math
The science of pharmacokinetics utilizes mathematical equations to describe the movement of the drug from the pill through the body, and finally into the urine and feces. These mathematical equations are similar to Einstein’s nature of energy E=mc2 or Pythagorean’s theorem a2+b2=c2. The equation used in pharmacokinetics is C(t)=C0e-kt, where C is the drug concentration, k is the rate of elimination, and t is the time since swallowing the pill.
It’s easy as apple pie! All you have to remember is that pharmacokinetics is the study of the movement of drug in the body.
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