Pharmacology

What does this Model Represent?

This applet models the concentration of a drug in the bloodstream as a function of time and the doses. Ideally, medicine would function best if it could maintain a constant concentration throughout the body, but this is not feasible. Instead, it is important for pharmacologists to set the dosages and timing such that the concentration of the drug stays within a certain range.

What are the elements of this Model?

The two quantities of note are the concentration of medicine in the intestines and that in the plasma. As medicine is taken in pill form, it first passes through the digestive system before reaching the bloodstream. From there, it slowly is excreted, requiring additional doses to maintain concentration.

How do I use this Model?

Set the variables for dosage per day and doses per day to determine the inputs of the drug. Then, the graph displays the medicine concentration over time.

What should I expect?

The concentration of the drug will rapidly increase after a pill is taken, then level off and slowly decrease until the next dose. Care must be taken to ensure that the concentration of the drug stays above the medicinal level whenever possible, but without exceeding the toxic level.

Download the model file.