Extended Release Drugs: Are They Right For You?

One of the biggest downsides to taking medication is side effects. After a dose of most medications, the amount in the bloodstream spikes quickly and then leaves the body within the course of a few hours. This means the amount of medication in the body can vary at any point in time — and that spike can mean unpleasant side effects.

This problem is exactly what extended-release (often noted as ER or XR) medications were designed for. Typically taken once a day, these formulations keep the dose at a steady level in the body for longer periods of time.

Read on to learn whether XR medications are right for you and important factors to consider.

How do extended-release (XR) drugs work?

Medications are usually broken down by the liver or kidneys, which means that after taking a dose, the body begins to naturally clear the medication from the system. As their name suggests, XR medications take longer to clear from the body than ordinary or immediate-release (IR) medications.

XR versions typically have special coatings or mixers to help the medication release over a longer period of time. Many popular medications are available as XR; for example, there are well over 30 for pain alone.

The graph below shows blood concentrations of the pain medication Ultram (tramadol) after taking the IR version (the white dots) every 6 hours, compared to the XR version (the dark dots), taken once every 24 hours.

Original data & chart published by DailyMed

Notice how the amount of medication in the bloodstream spikes for the IR medication. XR medications eliminate this problem. Though they typically take longer to kick in compared to their IR counterparts, XR medications maintain a more consistent level of the medication in your body. This could mean better treatment outcomes for longer periods of time while also lowering the chances of side effects. 

You also don’t have to take the medication as often, which may mean that you are less likely to forget to take your medication.

Is cost a barrier for XR medications?

While there are benefits to taking XR medications, not everyone takes them, due to the cost of these medications.

Typically, XR formulations go through a new drug approval process with the FDA and are granted an additional patent as a new drug. This means that an XR version may not have a generic alternative, making it more expensive.

But sometimes, XR versions are not expensive compared to their generic versions. For example, metformin ER has a generic form available, and its cost is almost the same as metformin IR.

Cost may also be a factor, depending on how often you need to take your medication. If you have health insurance, check which version of your medication may be covered and how much your copay would be. You can compare this with the lowest GoodRx price to see how you can save money on your medication.

Are XR drugs right for me?

If you are taking prescription medications every day, you should consult your healthcare provider or pharmacist to ensure you are taking the right form of medication. This may mean tracking your side effects and getting blood tests to find out the amount of medication that is right for you personally. 

There’s also a small chance that your body might not be able to break down the slow release coatings or ingredients fast enough to hit the targeted level of the medication in your bloodstream. So talk with a healthcare provider if you don’t think your health condition symptoms are improving.

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Written by:

Katie Mui

Katie Mui leads social impact efforts at GoodRx. She believes in health equity and the importance of patient advocacy and empowerment.

Edited by:

Samvida Patel, MNSP, INHC

Samvida Patel, MNSP, INHC, is a health editor at GoodRx. She is a nutritionist and integrative nutrition health coach with over 8 years of experience in health communications.

Reviewed by:

Christina Aungst, PharmD

Christina Aungst, PharmD, is a pharmacy editor for GoodRx. She began writing for GoodRx Health in 2019, transitioning from freelance writer to editor in 2021.

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References

U.S. Food and Drug Administration. (2017). List of extended release and long-acting opioid products required to have an opioid REMS.