An Overview of Decongestants

Relief for your cold and allergy symptoms

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A decongestant is a medication that clears up congestion (stuffy nose). You get stuffed up because of dilated (enlarged) blood vessels ​in your nasal and airway membranes.

They make it hard to breathe and can trap mucus. That compounds the problem. Decongestants narrow blood vessels. Then, mucus can drain and you can breathe.

When you feel stuffy, it's natural to expect a decongestant to help. But it might not always be the right choice.

This article will walk you through the types of decongestants, how they work, who shouldn't use them, how to take them, and side effects.

Closeup woman pouring medication or antipyretic syrup from bottle to cup
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Uses of Decongestants

Decongestants work best for minor congestion from:

They may not work as well for an infection. For that you need antibiotics. Then try decongestants for left-over stuffiness.


Dilated blood vessels cause congestion. Decongestant medications clear it up so you can breathe. They work bests on congestion from allergies or viruses. Infections should be treated with antibiotics

Types of Decongestants

Over-the-counter (OTC) decongestants come in oral forms (e.g., pills, tablets, capsules, liquids) and nasal sprays.

Combination products such as Tylenol Sinus, Advil Cold & Sinus, and Aleve Cold & Sinus also contain pain relievers. That may help with sinus headaches from congestion.

Common decongestants include:

  • Sudafed (pseudoephedrine)
  • Sudafed PE (phenylephrine)
  • Afrin and other nasal sprays (oxymetazoline)

Sudafed (Pseudoephedrine)

Sudafed and its active ingredient, pseudoephedrine, come in several forms:

  • Regular tablets
  • 12-hour and 24-hour extended-release tablets
  • Liquid solution

You can also buy generic pseudoephedrine. It's in many multi-drug cold and flu products.

OTC...Kind Of

Pseudoephedrine is technically available over the counter. So you don't need a prescription for it. But it's restricted due to its use in methamphetamines. You need to:

  • Ask for it at the pharmacy counter
  • Show your ID
  • Buy only in small quantities

Other brand-name drugs that contain pseudoephedrine include:

  • Contac Cold
  • Drixoral Decongestant Non-Drowsy
  • Kid Kare Drops
  • Nasofed
  • Sudodrin
  • Suphedrin
  • Unifed

This drug also prevents ear problems from pressure changes. That's helpful for flying or SCUBA diving.

Sudafed PE (Phenylephrine)

Sudafed PE and generic phenylephrine are also available in different forms:

  • Tablet
  • Liquid cough medicine
  • Quick-dissolve strip

Phenylephrine is also in many combination cold and flu products. It's also in some hemorrhoid treatments because it constricts blood vessels.

Other brand name products with phenylephrine include:

  • Actifed Cold and Allergy
  • Advil Congestion Relief
  • Pediacare Children’s Decongestant
  • Suphedrin PE

Phenylephrine hasn’t been used to make illegal drugs. So it’s not restricted.

Afrin Nasal Spray (Oxymetazoline)

Afrin and many other nasal sprays use the drug oxymetazoline. It's used for congestion and to relieve nasal discomfort from colds and seasonal allergies.

You spray oxymetazoline in your nose. The dosing schedule is typically every 10 hours or every 12 hours.

Other brands using oxymetazoline include:

  • Anefrin Nasal Spray
  • Dristan Nasal Spray
  • Mucinex Nasal Spray
  • Vicks Sinex Nasal Spray
  • Zicam Nasal Spray

It's also in many generic sprays.


Decongestants come in pills, liquids, and sprays. Common drugs are pseudoephedrine, phenylephrine, and oxymetazoline. Some have extended relief versions.

When using combination products containing decongestants, check labels before taking any other medications. It's not safe to double-up on them.

Who Shouldn’t Use Decongestants?

Most people can safely use decongestants. But they aren’t for everyone. Don't take decongestants if you have:

Always talk to your healthcare provider about all medications you take. That includes OTC drugs. They can help you avoid possibly dangerous side effects and drug interactions.

If you’re pregnant, trying to get pregnant, or breastfeeding, talk to your healthcare provider before taking decongestants.

Warning: Use in Children

Don't give decongestants to children under 6. Before giving them to kids between 6 and 12, talk to their healthcare provider.

How to Take Decongestants

Always follow the dosage instructions on the label or from your healthcare provider.

You can use most decongestants three to four times a day. Extended-release versions are used once or twice a day.

Nasal sprays work faster than oral decongestants. But don't use them for longer than recommended. They can irritate your nasal passages and make congestion worse.

Some products contain a decongestant and a painkiller. Check the label before taking these with any additional drugs. That'll keep you from doubling up on medications.

Your healthcare provider and pharmacist can tell you which drugs can (and can't) be safely combined.


If you have any chronic health conditions, check with your healthcare provider before using a decongestant. Don't give them to young children or take during pregnancy and breastfeeding without talking to your provider.

Side Effects

Decongestants may cause mild side effects. They include:

  • Nausea or vomiting
  • Nervousness
  • Restlessness
  • Weakness
  • Headaches
  • Dry mouth

Side effects specific to nasal sprays are:

  • Burning, stinging, or dryness inside the nostrils
  • Increased nasal discharge
  • Sneezing

More serious side effects should be reported to your healthcare provider immediately. They include:

  • Anxiety
  • Elevated blood pressure
  • Changes in heart rate or rhythm
  • Insomnia
  • Tremors
  • Severe dizziness or fainting
  • Numbness or pain in hands or feet
  • Hallucinations
  • Seizures
  • Psychosis
  • Urinary dysfunction

Decongestants may also contribute to strokes and intracranial (inside the skull) bleeding.

Decongestants are chemically related to adrenaline. That's your body’s natural decongestant and stimulant. Caffeine may enhance the stimulant effect and worsen side effects related to stimulants. Watch for nervousness and trouble sleeping.


Decongestants narrow the blood vessels that swell up and cause congestion. They're best against stuffiness or acute illnesses.

Decongestants come in many forms, including tablets, liquids, and nasal sprays. Always follow the dosage directions. When using multi-drug products, make sure you aren't doubling up with other medications you take.

Check with your healthcare provider about use in children, during pregnancy and breastfeeding, and with chronic conditions. Watch for side effects and contact your provider if you have any severe ones.

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8 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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