In this episode, I’ll discuss what I think is the best way to memorize pharmacology.
Have you ever noticed a clinician that seems to always have the ability to apply their knowledge to any patient scenario, no matter how complex?
I believe any pharmacist can achieve that ability by focusing on learning to correlate the mechanism of action of medications to the pathophysiology of disease. Once you reorganize your thinking to this method, you will be able to do the following with relative ease:
1. Anticipate indications and contraindications for new medications.
2. Correctly apply pharmacotherapy principles to any patient case, even if you have never encountered a particular combination of disease states before.
3. Remember what you have learned and apply it to the next patient without having to look it up every time.
An example of correlating the mechanism of action of medications to the pathophysiology of disease is how learning the pathophysiology of diabetic ketoacidosis leads to understanding the pharmacology of treating hyperkalemia.
How could these two disease states possibly be related? Let’s find out by exploring the mechanism of action of insulin.
In the presence of glucose, insulin forces glucose, potassium, and water inside cells. This explains why immediately treating elevated blood glucose from DKA with insulin could lead to cardiovascular collapse. Thinking about the mechanism of action & pathophysiology makes it clear why – all of that glucose will pull water from the intravascular space into the intracellular space when insulin is given. This will result in severely reduced blood volume and potentially catastrophic consequences.
Now it becomes clear why adequate fluid resuscitation, and not insulin, should be the immediate priority when caring for a patient with DKA.
Where does hyperkalemia fit in? Insulin (given with dextrose to prevent hypoglycemia) will bring potassium into the cell, where it cannot adversely affect the electrical conduction of the heart. This is a temporary shift in the potassium location, but will buy enough time for a definitive plan to remove excess potassium from the patient (for example dialysis, or administration of an anion exchange resin).
You can download a free PDF of 5 additional examples of the technique of correlating mechanism of action to pathophysiology of disease inside my free download area at pharmacyjoe.com/free.
If you like this post, check out my book – A Pharmacist’s Guide to Inpatient Medical Emergencies: How to respond to code blue, rapid response calls, and other medical emergencies.