I visited my mom last weekend. I traveled to Washington, DC for a meeting and decided to stop in Cocoa Beach, Florida on my way back to Denver. Although the Florida regulars still considered it cold, the snowbirds and I thought it was very pleasant.
Two of the highlights of visiting at that time were that my grandson and family were visiting on their way to Disney, as well as my Aunt Terri, whom I have not seen in years and simply do not see enough of. She was visiting my mom with her husband George.
As a proud mother, my mom keeps my book, Understanding Drug Action: An Introduction to Pharmacology on her coffee table. So Terri and George were reading about their medications and said the book helped them understand enough to ask questions once I arrived.
George is taking an antiarrhythmic drug which is expensive; if he can’t find a cheaper way to get it, he’d like his doctor to consider changing to another less expensive drug. Sounds like a simple enough issue, but let’s consider it.
Some drugs are easier to swap than others. Consider a drug for high blood pressure. You can have your blood pressure measured at any time to assess that your hypertension medicine or combination of medicines is working. Your prescriber can make dosage choices based on your individual response to your medications.
A medication that produce directly and easily measured responses are dosed individually based on response.
These include most drugs for hypertension, diabetes, thyroid and many other diseases states. These are the easy drugs to dose and fairly easy drugs to switch.
Now consider a drug like a seizure medication. With severe seizures, it might be easy to adjust medication dosage as we can count the decreasing number of seizures that each patient experiences. But what about when we get to the final dosing when the goal is no seizures at all. Would a dose that allowed one seizure a week be considered OK? One seizure a month? One seizure a year? Probably not ideal.
Drugs responses that are considered all-or-none include responses like seizures, pregnancy, arrhythmias and sleep.
They either happen or they don’t. And since it’s much harder to adjust the dosage using individual patient responses, these drugs are typically dosed based on population responses. For example, if we keep track of what percentage of patients experience a seizure while taking dosages of seizure medication, we find that there is an optimal dosage at which most patients who will respond successfully are helped without experiencing unacceptable side effects (like sleepiness, incoordination or slurred speech for seizure meds).
So, medications for all-or-none responses are dosed to provide the maximum benefit and minimum risk as measured in large groups of patients using the drugs.
Back to George:
Arrhythmias are also an all-or-none response, except that we can’t see arrhythmias and they can result in a heart attack; that would be bad. Drugs for arrhythmia are similar to drugs for seizures in that there are several classes of medications with different mechanisms and they have to be dosed based on population responses. In George’s situation, there may be a certain risk in trying to change from a drug that is working to another less expensive drug that might work as well, but also might not work.
Many patients have questions about their medications, particularly when it comes to the question, “will another less expensive drug work just as well?”
Your prescriber will be the final authority, but your pharmacist can help you understand the cost difference and the therapeutic differences in terms of effectiveness and side effects. Your pharmacist may be able to recommend the best alternatives to consider for your medications. If you have concerns or are unsure about your medications, your local pharmacist is always there to help. Take care of your health!