Accidentally Took Two Propranolol Extended-Release Capsules

In our latest question and answer, the pharmacist discusses what to do if you accidentally took two doses of propranolol ER.

Question

I accidentally took 2 doses 60 mg of propranolol XR yesterday (last dose 2:00 pm). Should I take my regular dose of 60 mg today or wait until tomorrow morning?

Asked by Mareva On Dec 11, 2022

Answered by
Medical Content Reviewed By HelloPharmacist Staff

Published Dec 12, 2022
Last updated Apr 23, 2024

Key points

  • Taking two propranolol extended-release capsules may increase your risk of side effects, such as low blood pressure, dizziness, and drowsiness. Serious side effects would be uncommon be sure to seek medication if they occur.
  • For most individuals, you want to continue taking your propranolol as prescribed, even if you took an extra dose since most of the drug will be out of your system by the time of your next dose.

Answer

Thanks for reaching out to us! It's always a good idea to ask a medical professional what to do in situations like these, as the answer can vary depending on the drug.

As it concerns propranolol, first and foremost, it is important to know that taking an extra dose is unlikely to cause any serious harm. You'll likely experience some mild side effects, like drowsiness, dizziness, low blood pressure, and a reduced heart rate for a few hours, but I wouldn't expect anything major.

I do think it's important to point out that you should take it easy for the day, and try not to move around too quickly, especially when going from a seated/lying down position to a standing one.

Taking too much propranolol would put you at a greater risk of orthostatic hypotension, which is a drop in blood pressure when you stand up too quickly (it's the moment of lightheadedness and dizziness that we've all experienced).

Orthostatic hypotension can cause you to be unbalanced and potentially fall, so again, take it easy.

If you are feeling any more serious side effects from your extra dose, I highly recommend seeking medical attention, or, at the very least, contacting the Poison Control Center (1-800-222-1222; Poison.org).

What To Do For Your Next Dose

You don't mention how you are taking your propranolol extended-release, but it is most commonly dosed once daily.

For most individuals, you'll want to take your next dose as scheduled the next day and do not skip it, even though you took an extra dose the day before.

Taking a higher dose at one time doesn't mean it will last longer in your system. For the vast majority of drugs, they are metabolized over the same period of time regardless of the dose you took. For example, your body will metabolize 325mg of Tylenol in the same amount of time it would take to metabolize 650mg of Tylenol.

The half-life of propranolol is around 3 to 6 hours, and this is the time in which it takes your body to metabolize half of the drug, regardless of the dose. After 4-5 half-lives, the drug would be considered almost completely metabolize and eliminated from your system.

By the time your next dose of propranolol is due, most of the drug will already be out of your system.

Final Words

Thanks so much for reaching out! We're always happy to help.

References

  • Propranolol Monograph, PubMed
  • Inderal LA Prescribing Information, DailyMED

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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