Does Metamucil Expire?

In our latest question and answer, the pharmacist discusses whether or not the fiber supplement Metamucil expires.


Does Metamucil expire? What happens to fiber if it is expired?

Asked by Wonderboy On Sep 12, 2022

Answered by
Medical Content Reviewed By HelloPharmacist Staff

Published Sep 12, 2022
Last updated Jul 18, 2024

Key points

  • Metamucil, like all drug and supplement products, does expire.
  • For most Metamucil products, the expiration date to 2 years or so from the date of manufacture.


Metamucil is a fiber supplement and bulk-producing laxative.  It can be used for constipation and as a supplement to increase fiber in a person's diet.  Like all drug and supplement products, it does expire.

Metamucil Expiration

All drugs and supplements are required by the FDA to have an expiration date, Metamucil included.  Drug manufacturers are required to test for a drug's stability.  This means the manufacturers must prove that a drug keeps its strength, purity, and quality until the expiration date.  

Part of this also includes the establishment of the proper storage conditions for the drug.  Incorrect storage of a drug can lead to changes in the drug's stability.  So it is very important to pay attention to the temperature requirements of a drug and to generally store a drug in dry cool conditions.

According to Metamucil's manufacturer, Metamucil should not be used past its expiration date.  

All Metamucil products should have an expiration date on the packaging, typically around 2 years after the date of manufacture.

Should Metamucil be expired, it should be disposed of in the garbage according to the manufacturer. Once a drug product has expired, there is no guarantee the drug will work as it has intended. It could possibly be less than effective, especially if not stored according to manufacturer recommendations.

What Happens To Expired Metamucil?

There could be a number of issues with expired Metamucil products. For one, the storage conditions may no longer be ideal. Over time, the seal on the product may break down, and the powder may be exposed to air, humidity, moisture, etc, which could degrade its quality.

Additionally, there is always the risk of microbial exposure over time, which could make the product no longer suitable, or safe, to take.

There is no way to accurately determine how long a Metamucil product is good for after the expiration date. Sure, in all likelihood, taking a recently expired Metamucil product may be perfectly safe and effective, but, to be safe, you should only take a product that is in-date.

Final Words

Remember, all drugs approved by the FDA have expiration dates. Drugs should not be used past expiration dates due to concerns of the safety, stability, and purity of a drug.

If a drug is expired, it should be disposed of properly.  If there are any questions about this, please contact your local pharmacist for the correct disposal of medications. 

Thanks for reaching out to us!


  • Expiration Dates - Questions and Answers, FDA
  • Metamucil Manufacturer Website, Metamucil

About the Pharmacist

Dr. Brian Staiger, PharmD

Dr. Brian has been practicing pharmacy for over 13 years and has wide-ranging experiences in many different areas of the profession. From retail, clinical, program development, and administrative responsibilities, he's your knowledgeable and go-to source for all your pharmacy and medication-related questions! Dr. Brian Staiger also has herbalist training and educational certificates in the field of medical ethnobotany. Feel free to send him an email at [email protected]! You can also connect with Dr. Brian Staiger on LinkedIn.

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