Can You Take Sudafed And DayQuil Together?

In our latest question and answer, the pharmacist discusses if DayQuil and Sudafed can be used together.


I have terrible nasal congestion. I usually use Sudafed to help. I think I have a cold too, so I want to use DayQuil. Is that safe to combine?

Asked by Lionel On Nov 22, 2022

Answered by
Medical Content Reviewed By HelloPharmacist Staff

Published Nov 22, 2022
Last updated Nov 22, 2022

Key points

  • Most DayQuil products, including the 'original' DayQuil and DayQuil Severe, already contain a decongestant (phenylephrine) and should not be taken with Sudafed.
  • It is important to look at all the drugs contained in any over-the-counter product you are considering taking to make sure you are not getting too much of one drug.


Thanks for reaching out! When considering taking multiple OTC (over-the-counter) products, it is extremely important to pay attention to the drugs contained in each one. Always check the 'Drug Facts' label as many products contain multiple drugs, and it can be relatively easy to accidentally take too much of one thing.

DayQuil is a good example of a product that contains multiple drugs. In fact, there are a variety of 'DayQuil' products, and they all contain different drugs.

Most DayQuil products should not be taken with Sudafed as nearly all of them already contain a nasal decongestant.

It is important to note that when referring to 'Sudafed', you may be referring to the original product, which contains pseudoephedrine (and is purchased at the pharmacy counter) or Sudafed PE (phenylephrine), which can be purchased over-the-counter without ID.

Regardless of which Sudafed product you are talking about, you should not combine multiple decongestants due to the increased risk of side effects (which includes headache, increased heart rate and increased blood pressure).

Most DayQuil Products Already Contain A Decongestant

The 'original' DayQuil contains the following ingredients:

  • Acetaminophen (pain reliever)
  • Dextromethorphan (cough suppressant)
  • Phenylephrine (nasal decongestant)

DayQuil With Active Ingredients

Another product in the DayQuil family, 'DayQuil Severe', also contains a decongestant:

  • Acetaminophen (pain reliever)
  • Dextromethorphan (cough suppressant)
  • Phenylephrine (nasal decongestant)
  • Guaifenesin (expectorant)

Do Any DayQuil Products Not Contain A Decongestant?

'DayQuil High Blood Pressure Cold & Flu' does not contain a decongestant, but that is because it is intended for those trying to avoid decongestants as they have been linked to causing high blood pressure.

Data is mixed in this regard, but as a general rule of thumb, it is recommended to avoid taking nasal decongestants if you have high blood pressure unless specifically recommended by your doctor.

Alternative Options

So, as shown in the sections above, most DayQuil products already contain a decongestant and therefore should not be taken with Sudafed.

However, DayQuil only has a duration of action of around 4 to 6 hours per dose, so you could certainly separate your dosing of DayQuil and Sudafed by that amount of time and avoid an interaction.

Additionally, you could skip DayQuil altogether and only choose over-the-counter products with single drugs that you need to help treat your symptoms (e.g., Tylenol for aches/pains, Sudafed for nasal congestion, Mucinex for chest congestion, etc...).

The most important thing to remember when choosing over-the-counter cough/cold products is to avoid taking double-dosing on the same drug (or drug class). It's unfortunately all too common (and one of the main reasons for accidental acetaminophen overdoses).

Final Words

I hope you found this helpful! Reach back out again anytime.


  • Risk of Unintentional Overdose with Non-Prescription Acetaminophen Products, PubMed
  • DayQuil Manufacturer Website, Vicks
  • Pseudoephedrine Sulfate Monograph, PubChem

About the Pharmacist

Dr. Brian Staiger, PharmD

Dr. Brian has been practicing pharmacy for over 11 years and has wide-ranging experiences in many different areas of the profession. From retail, clinical and administrative responsibilities, he's your knowledgeable and go-to source for all your pharmacy and medication-related questions! Feel free to send him an email at! You can also connect with Dr. Brian Staiger on LinkedIn.

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