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Drug

Pseudoephedrine-Guaifenesin

Pronounced

"gweye-FEN-eh-sin/sue-doh-eff-ED-rin"

Uses

This combination medication is used to temporarily treat cough and runny/stuffy nose (nasal congestion) caused by infections (such as the common cold), allergies (such as hay fever), and other breathing illnesses. This product is usually not used for ongoing cough from smoking or long-term breathing problems (such as chronic bronchitis, emphysema) unless directed by your doctor. Guaifenesin is an expectorant. It works by thinning and loosening mucus in the airways, clearing congestion, and making breathing easier. Pseudoephedrine is a decongestant (sympathomimetic). It reduces nasal congestion by narrowing the blood vessels in the nose.

If you are self-treating with this medication, it is important to read the package instructions carefully before you start using this product to be sure it is right for you. (See also Precautions section.)

Cough-and-cold products have not been shown to be safe or effective in children younger than 6 years. Do not use this product to treat cold symptoms in children younger than 6 years unless specifically directed by the doctor. Some long-acting products are not recommended for use in children younger than 12 years. Ask your doctor or pharmacist for more details about using your product safely.

These products do not cure or shorten the length of the common cold and may cause serious side effects. To decrease the risk for serious side effects, carefully follow all dosage directions. Do not give other cough-and-cold medication that might contain the same or similar ingredients (see also Drug Interactions section). Ask the doctor or pharmacist about other ways to relieve cough and cold symptoms (such as drinking enough fluids, using a humidifier or saline nose drops/spray).

How to Use This Medication

Take this medication by mouth with or without food, usually every 12 hours with a full glass of water or as directed by your doctor. If stomach upset occurs, take with food or milk. If you are self-treating, follow all directions on the product package. To prevent trouble sleeping, do not take this medication close to bedtime. If you have any questions, ask your doctor or pharmacist.

Swallow the capsules whole and do not open them. Do not crush or chew the capsules or tablets. Doing so can release all of the drug at once, increasing the risk of side effects. Also, do not split the tablets unless they have a score line and your doctor or pharmacist tells you to do so. Swallow the whole or split tablet without crushing or chewing.

The dosage is based on your age, medical condition, and response to treatment. Do not take more than 2 doses in a day. Do not increase your dose or take this drug more often than directed.

Drink plenty of fluids while taking this medication. Fluids will help to break up mucus and clear congestion.

Caffeine can increase the side effects of this medication. Avoid drinking large amounts of beverages containing caffeine (coffee, tea, colas), eating large amounts of chocolate, or taking nonprescription products that contain caffeine.

Tell your doctor if your condition is accompanied by a headache that doesn't go away, fever, severe sore throat, rash, or if it lasts, returns, or gets worse after 7 days. These may be signs of a serious medical problem. Get medical help right away if you think you may have a serious medical problem.

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Drug information is selected from data included with permission and copyrighted by First DataBank, Inc. This is a summary and does not contain all possible information about this product. For complete information about this product or your specific health needs, ask your healthcare professional. Always seek the advice of your healthcare professional if you have any questions about this product or your medical condition. This information is not intended as individual medical advice and does not substitute for the knowledge and judgment of your healthcare professional. This information does not contain any assurances that this product is safe, effective or appropriate for you.

This information is intended only for residents of the United States. Products sold under the same brand names in other countries may contain different ingredients.

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Information expires December 2025.