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What Is Pseudoephedrine, the Active Ingredient in Many SUDAFED® Products? And What Is It Used For?

Pharmacist showing older customer medication

Congestion can occur suddenly, whether it’s caused by a cold or allergies. Whatever the case, the feeling of congestion can be very unpleasant, and you’ll likely want to find an effective way to relieve congestion fast.

Pseudoephedrine, an active ingredient in many behind-the-counter nasal decongestants, can help provide that much-needed relief from blocked or stuffy airways, making it easier for you to breathe and get back to your day-to-day.

But how exactly does pseudoephedrine work? Are there any side effects? And what’s the recommended dosage?

To answer these questions, let’s take a deep dive into pseudoephedrine – the active ingredient in many SUDAFED® products – and see how it can help you clear a stuffy nose and congestion.

What Is Pseudoephedrine?

Pronounced soodōˈefədrēn, ’pseudoephedrine’ is an active ingredient in nasal decongestant products, such as SUDAFED® and it helps relieve congestion.

The congestion symptoms pseudoephedrine can help clear may be caused by the common cold, hay fever – or even everyday upper respiratory allergies.

Pseudoephedrine-containing decongestants are packaged in pill or liquid form and can only be found behind-the-counter at your local pharmacy or drug store.

How Does Pseudoephedrine Work?

When your body detects an ‘intruder’, such as a virus or allergens as mentioned above, it reacts by directing extra blood to the blood vessels in the nose. This causes the blood vessels and tissue to swell, which can make your nose feel stuffy – and harder to breathe through.

Pseudoephedrine acts by narrowing these blood vessels and shrinking the swollen tissue, so that air can pass through the sinuses freely. This results in your nasal passages feeling cleared and easier breathing.

What Is Pseudoephedrine Used For?

Pseudoephedrine is used to help relieve the following symptoms:

These symptoms are often the result of the common cold, hay fever, or upper respiratory allergies.

Why Is Pseudoephedrine Medication Only Available for Behind-The-Counter Purchase?

When taken as directed, pseudoephedrine is considered a safe and effective medication. However, pseudoephedrine is only available behind the counter at drug stores and pharmacies because there is a limit on the total quantity that can be purchased by any one individual to prevent potential misuse.

But what does it mean if a product is behind-the-counter at a retailer? Well, simply put, it means that you, as a customer, won’t have direct unchecked access to the product – and will first have to speak with a pharmacist or drug store employee before purchasing the medication.

Federal law also regulates the sale of products containing pseudoephedrine as an active ingredient by:

  • Limiting the amount that a person can purchase every month

  • Specifying a minimum age of purchase, and requesting proof of government-issued photo identification

Just remember to consult your pharmacist or doctor if you have any questions or you’re looking to purchase a pseudoephedrine containing product.

What Can You Tell Me About the Safety Profile of Pseudoephedrine?

Pseudoephedrine is considered safe and effective when taken as directed. Indeed, the FDA recognizes it as an effective treatment for congestion caused by allergies, hay fever, and the common cold.

That said, it is important to remember that you should not use a pseudoephedrine decongestant alongside a prescription of monoamine oxidase inhibitor (MAOI), or two weeks after stopping any medicine that is considered an MAOI.

MAOIs are certain drugs used to treat psychiatric/emotional conditions, depression and Parkinson’s disease.

If you’re unsure whether your prescription medication contains MAOI, speak to your pharmacist or doctor.

You should also contact your doctor before using pseudoephedrine if you have any of the following conditions:

  • Trouble urinating because of an enlarged prostate

  • Diabetes

  • Thyroid disease

  • High blood pressure

  • Heart disease

Stop using the product and ask a doctor if you experience any of the following while taking SUDAFED®:

  • You experience nervousness, dizziness or sleeplessness

  • Your symptoms occur with a fever, or do not improve within seven days

  • You experience persistent abdominal pain or vomiting

Speak to your doctor before using pseudoephedrine if you’re pregnant or breast-feeding.

Always read and follow the instructions on the product label if using a multi-ingredient medicine containing pseudoephedrine, such as SUDAFED®, to ensure you do not exceed the recommended dosage.

Dosage Information for Pseudoephedrine

Make sure to carefully read and follow the directions on the product package label before taking any pseudoephedrine-containing products. This will let you know how much of the medicine to take, and how often to take it. If you have any further questions or concerns, contact your doctor or pharmacist.

Visit our online SUDAFED® Dosage Guide.

Pseudoephedrine Dosing: What You Need to Know

  • Pseudoephedrine is available for both children and adults. Follow specific package directions for each product. Consult your pharmacist or doctor with any dosing questions.

  • If you are taking pseudoephedrine medicine in liquid form, always use the cup that comes with the medication to measure your dose. Do not use a household spoon

  • Do not break, chew or crush pseudoephedrine medicine that comes as extended-release tablets. Always swallow them whole

  • If your symptoms do not improve within seven days of taking pseudoephedrine, or occur with fever stop taking the medication and contact your doctor

  • In case of an overdose, contact an emergency room or poison control center right away

Always read and follow the product label of a pseudoephedrine-containing product.

For more information on SUDAFED® products, dosage and directions, you can check out the SUDAFED® Dosage Information page.

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