Sudafed Drug Profile and Side Effects

Uses, Side Effects & More

Johnson & Johnson's Sudafed
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Sudafed is nasal decongestant used to treat congestion. Because it was being widely abused as a raw ingredient in methamphetamines, Sudafed is now located behind the counter, but it doesn't require a prescription. Simply ask your pharmacist, show a photo ID and sign upon purchase.

Sudafed PE, however, is sold on drugstore shelves. That's because Sudafed and Sudafed PE are made with different formulations.

In 2006 the FDA passed a law that requires Sudafed to be sold behind the counter because its active ingredient is pseudoephedrine, which is used to manufacture illegal methamphetamines. Sudafed PE, however, is available over-the-counter. Its active ingredient is phenylephrine.

What is Sudafed?

The active ingredient in Sudafed, pseudoephedrine, is used to alleviate nasal congestion caused by allergies, colds, and other upper respiratory illnesses. It can also be used to relieve sinus congestion and pressure caused by sinusitis, or a sinus infection.

Congestion occurs when blood vessels in the nasal passages and airways swell and expand, becoming inflamed. Sudafed works by shrinking the blood vessels back to their normal size to allow more airflow and mucus to drain. It is used to relieve symptoms, not to treat the causes of symptoms or to speed up recovery.

Adults and children over 12 years old should take two caplets every 4 to 6 hours, not to exceed four doses in 24 hours.

Children ages 6 to 12 years old should take one caplet every 4 to 6 hours, not to exceed four doses in 24 hours. Children under 6 years should never take Sudafed unless directed to do so by a doctor. Sudafed should also be swallowed whole. Do not crush or chew Sudafed.

  • What Are the Side Effects of Sudafed?

    Sudafed and other decongestants typically do not cause any side effects, and if side effects occur, they're usually mild. Still, it's important to know that side effects are possible. The chemical formulation of Sudafed is similar to adrenaline, which, in addition to acting as a natural decongestant, is also a stimulant. Taking a decongestant such as Sudafed can make a person feel jittery, and it can also impact a person's blood pressure, pulse and ability to fall asleep, although this isn't common.

    Common side effects of Sudafed include:

    • Confusion
    • Nervous feeling
    • Headache
    • Nausea
    • Vomiting
    • Loss of appetite
    • Restlessness

    Other side effects of Sudafed are more serious. If you experience any of the following, contact your doctor immediately:

    • Dizziness
    • Stomach pain
    • Difficulty breathing
    • A fast, pounding or irregular heartbeat
    • Nervousness
    • Sleeplessness
    • Nasal congestion that lasts for more than 7 days or is accompanied by a fever

    Should Anyone Not Take Sudafed?

    Sudafed and other decongestants are safe for most people, but there are some exceptions. Do not take Sudafed without your doctor's permission if you have any of the following:

    • Heart disease
    • High blood pressure
    • Thyroid disease
    • Diabetes
    • Prostate issues
    • Are pregnant or planning to become pregnant
    • Are breastfeeding

    Additionally, you should not use Sudafed if you are currently taking a MAOI or for the 2 weeks after you stop use of an MAOI. If you have any questions or hesitations, talk to your doctor or pharmacist before taking this medication. 

    Keep Sudafed and all other medications, for that matter, out of reach from children. In the case of an overdose, contact Poison Control or visit an emergency room immediately.


    NHS Choices. Decongestants. (2016, March 03). 

    "Products/Sudafed Nasal Decongestant." Sudafed & Sudafed PE. 2005. Pfizer Inc. 22 Jan 2007.

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