Decongestants for Allergic Rhinitis

Search Knowledgebase

Decongestants for Allergic Rhinitis


Many over-the-counter decongestants are available. The following are a few examples:

Generic NameBrand Name
oxymetazoline hydrochlorideAfrin
phenylephrine hydrochlorideDimetapp, Theraflu Cold and Flu
pseudoephedrine hydrochlorideSudafed

Decongestants are available as nasal sprays, liquids, and pills.

In some provinces, medicines containing pseudoephedrine (such as Sudafed) are kept behind the pharmacist's counter or require a prescription. You may need to ask the pharmacist for it or have a prescription from your doctor to buy the medicine.

How It Works

Decongestants narrow blood vessels, reducing the blood supply to nasal mucous membranes. This reduces stuffy and runny noses.

  • Pill decongestants narrow blood vessels not only in the nose but also in other parts of the body, which can cause side effects such as high blood pressure and nervousness.
  • Nasal decongestant sprays narrow blood vessels only in the nose and not in other parts of the body, so they rarely cause the side effects that pill decongestants do.
  • You can use nasal decongestant sprays only for a few days. If you use them longer than this, your nasal congestion may get worse (rebound congestion). Using a nasal decongestant continually to avoid rebound congestion can result in dependence on the medicine.

Why It Is Used

You can use decongestants for a stuffy or runny nose caused by allergic rhinitis.

How Well It Works

Nasal spray decongestants work within about 10 minutes and may provide relief for up to 12 hours. Pill decongestants work within 30 minutes and may provide relief for up to 6 hours.

Decongestants do not help sneezing or itching. But some pill decongestants are combined with an antihistamine to help sneezing and itching. Examples include Actifed.

Side Effects

If you use too much nasal decongestant spray, or if you use it for too long, rebound congestion may occur between uses or after you stop using it.

Side effects of decongestant pills may include:

  • High blood pressure.
  • Trouble sleeping (insomnia).
  • Feeling nervous or grumpy.
  • Headache.
  • Increased pulse rate (tachycardia).

In men with an enlarged prostate, use of decongestants may cause difficulty urinating.

See Drug Reference for a full list of side effects. (Drug Reference is not available in all systems.)

What To Think About

  • Pill decongestants have little effect on blood pressure when used as directed. But if you have uncontrolled high blood pressure, you should not use these medicines.
  • If you have coronary artery disease, diabetes, or thyroid problems, talk to your doctor before you use decongestants.
  • If you have glaucoma or other conditions that cause increased pressure inside the eye, talk with your ophthalmologist before you use decongestants.
  • If you are taking tricyclic antidepressants or monoamine oxidase inhibitors (MAOIs), which are sometimes used to treat depression and migraine headaches, talk with your doctor before you use decongestants.
  • Do not use decongestant nasal sprays for more than 3 days in a row.
  • Overdose of pill decongestants can cause high blood pressure, nervousness, kidney failure, heart rhythm problems, strokes, and seizures.
  • Many over-the-counter medicines for other health problems, such as some diet pills, contain decongestants. Avoid taking two medicines that contain decongestants at the same time because of possible overdose.
  • Purchased or homemade saltwater (saline) nasal sprays may also help clear up a stuffy nose. See cleaning your nasal passages with salt water.
  • Before you give decongestant medicines to a child, check the label. These medicines are not recommended for children younger than age 6.

Complete the new medication information form (PDF) (What is a PDF document?) to help you understand this medication.


By Healthwise Staff
Primary Medical Reviewer E. Gregory Thompson, MD - Internal Medicine
Specialist Medical Reviewer Harold S. Nelson, MD - Allergy and Immunology
Specialist Medical Reviewer Brian D. O'Brien, MD - Internal Medicine
Last Revised November 21, 2010

This information does not replace the advice of a doctor. Healthwise, Incorporated disclaims any warranty or liability for your use of this information.