Search info


How can decongestants relieve cold and flu symptoms?


A decongestant is a medication that helps to relieve symptoms of the cold and flu, particularly congestion. Decongestants help to clear congestion by tightening blood vessels in the nose. This quells swelling so that more air is able to pass through, allowing you to breathe more easily. Decongestants are available over the counter in most states in spray, drops, liquids, or tablets.

Do decongestants have any side effects?

Usually, decongestants do not cause any severe side effects. Occasionally, however, decongestants may lead to side effects like sleeping problems, dizziness, nervousness, heart palpitations, and high blood pressure. If any of these symptoms become severe, or if you experience any other abnormal side effects, you should contact your doctor right away.

Who should not take decongestants?

You should not take decongestants if you are allergic to any of the elements contained in these types of medications. Additionally, certain medical conditions and medications may increase your risk for complications associated with decongestants. These medical conditions include prostate issues, thyroid issues, diabetes, heart conditions, glaucoma, and high blood pressure.

How do decongestants interact with other medications?

Certain medications may increase your risk for complications associated with decongestants. Medication that may increase your risk for complications include other cough and cold medications, blood pressure medications, MAOIs, and diet pills. Before taking this, or any other medication, you should talk to your doctor about all of the risks for interaction.

How should I take decongestants?

Because there are so many different types and combinations of decongestants, there are also many different ways to take it. You should follow the directions of your doctor and the instructions printed on the medication container. When you first begin taking decongestants, you should not participate in any activities that require alertness, such as driving, until you know how the medication will affect you.

Should I let my doctor know I am taking decongestants?

If you are planning on taking decongestants, you should talk to your doctor. In fact, you should always let your doctor know about any medication you are taking so that you avoid any interactions with other medications. Decongestants, in particular, can react adversely with a variety of different medical conditions, medications and foods. Thus, it is important to discuss the proper dosage of decongestants and all of the possible complications that may accompany it.

View decongestant products.

View cold and flu relief products.

Arm yourself with a flu shot.

Back to Ask a Pharmacist


Answers to questions regarding information about medications or health conditions are not for diagnostic or treatment purposes and are not conclusive as to the presence or absence of any health condition. Consult your physician for diagnosis and treatment of your medical condition. The information provided is not a substitute for medical advice. Advances in medicine may cause this information to become outdated, invalid or subject to debate. Professional opinions and interpretations of the scientific literature may vary. Walgreens' terms of use and general warranty disclaimer apply to all services provided. If you are in need of immediate medical attention, contact your physician, poison control center or emergency medical professional. If you need to speak with a pharmacist for non-emergency matters, contact your local Walgreens pharmacist or call a pharmacist toll-free at 1 (877) 250-5823.

Balance Rewards for Healthy Choices

20 Points
20 Points

Now you can track your blood pressure and blood glucose.

Start earning points Go Arrow