Medication Adherence: Definition, Tools, & Statistics

Instructor: Danielle Haak

Danielle has a PhD in Natural Resource Sciences and a MSc in Biological Sciences

Medication adherence refers to taking prescription medications correctly. There are many reasons people might not follow their doctor's directions, and we'll take a look at some of these here, as well as some tools you can use to make adherence easier.

Medication Adherence

Grandma has 23 different medications she takes each month! Though she wasn't faced with suddenly taking these all at once - they gradually accumulated in number over time - it took her awhile to figure out a way to keep all of them straight. How could she make sure she was taking each medicine at the right time and at the right dosage?

Taking medications correctly and as prescribed is called medication adherence. This includes taking the correct dosage at the right time(s) each day and getting prescriptions refilled in a timely fashion.

Why might people not take their medications properly? There are a few common reasons. First, as in the case with Grandma, there were simply too many medications for her to keep track of! There had to be an easier system for her to track each one. Even with fewer than 23 medications, it's easy for patients to get confused about the dosage and timing of their medications. Patients who change medications a lot may also get their current medication schedule confused with old ones.

Another reason people may not adhere to their medical guidelines is because they can't afford the costs associated with their prescription medications. You can't get a prescription filled if you can't pay for it. Additionally, poor communication between doctor and patient may leave a patient feeling unprepared for the side effects they experience from a medication. Finally, the patient may not understand why they are taking a certain medication or they may not believe it's working.

Medication adherence is a constant battle for healthcare workers.
prescription medications

Statistics on Medication Adherence

The World Health Organization (WHO) estimated in 2003 that approximately half of all patients in developed countries do not take their prescriptions as prescribed by their doctors, resulting in more health problems or even death. If we translate the direct costs associated with 50% adherence, it ranges from $100-$289 billion per year.

We can break these numbers down a little bit more. It's estimated that between 20%-30% of all prescriptions are never even filled, and about 50% of long-term prescriptions are not taken correctly. There's evidence that patients may start out following their medication directions, but that adherence declines after about 6 months, which can lead to this drop in getting prescriptions refilled regularly.

A 50% adherence rate sounds extreme, but it would help to understand how many people are really affected. The WHO also estimates that, in the next 5 years, almost half of all Americans will suffer from at least one chronic ailment that requires ongoing medication use. Thus, of the roughly half of all Americans who are on medications, about half of them will not take their medication properly. That translates to a quarter of the US population failing to take their prescription medication properly. That's a lot of people!

Improving Medication Adherence

Many healthcare workers realize the importance of medication adherence and take steps to improve these rates. One easy-to-remember acronym is SIMPLE. Let's look at what this means.

S: simplify the directions or regimen as much as possible. This might include changing the number of medications or aligning the frequency and timing of doses as much as possible.

I: impart knowledge to clearly state the importance of maintaining a consistent medication schedule. This may require communication with other family members or caregivers. Providing both a verbal and written description also helps.

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