Taking Robitussin DM With Sudafed

In our latest question and answer, the pharmacist discusses whether or not Robitussin DM can safely be taken with Sudafed.


Can I take Robotussin DM and Sudafed 12 hr at the same time?

Asked by Katie On Mar 11, 2018

Answered by
Medical Content Reviewed By PharmacistAnswers Staff

On Mar 13, 2018

Sudafed (pseudoephedrine) and Robitussin DM (guaifenesin & dextromethorphan) can safely be taken together. There is no interaction between the medications. In fact, the use of both together is often recommended if you have the following symptoms:

  • Nasal congestion
  • Sinus pressure
  • Cough
  • Chest Congestion

Below, we discuss Sudafed and Robitussin DM in more detail.


Sudafed (pseudoephedrine) is a commonly used nasal decongestant that works by producing vasoconstriction in the nasal passages, which shrinks swollen nasal membranes and relieves nasal congestion. Sudafed also acts to increase nasal airflow and drainage of sinus secretions.

Sudafed is typically well tolerated, but one of the most common adverse reactions to it is insomnia. Sudafed can have a slight stimulating effect in some, making it difficult to fall asleep easily. In fact, insomnia has a reported incidence rate of between 4% to 10% based on data obtained from studies. Therefore, it is important to take Sudafed earlier in the day to prevent insomnia.

Robitussin DM

Robitussin DM is a combination cough/cold medication and contains the following ingredients:

  • Guaifenesin
  • Dextromethorphan

Guaifenesin is classified as an expectorant and helps to thin mucus and reduce mucus viscosity. Dextromethorphan is a cough suppressant and helps to reduce the frequency and severity of cough.

Taking Sudafed With Robitussin DM

As mentioned above, Sudafed and Robitussin DM can safely be taken together. There is no interaction between the two medications.

About the Pharmacist

Dr. Brian Staiger Pharm.D

Dr. Brian Staiger is a licensed pharmacist in New York State and the founder of PharmacistAnswers.com. He graduated from the University At Buffalo with a Doctor of Pharmacy degree in 2010. He has been featured in numerous publications including the Huffington Post as well as a variety of health and pharmacy-related blogs. Please feel free to reach out to him directly if you have any inquiries or want to connect! He's answered thousands of medication and pharmacy-related questions and he's ready to answer yours! Brian.Staiger@PharmacistAnswers.com Office: 716-389-3076

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