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12 Hour Cold Side Effects

Generic name: dexbrompheniramine / pseudoephedrine

Medically reviewed by Drugs.com. Last updated on Jun 30, 2022.

Note: This document contains side effect information about dexbrompheniramine / pseudoephedrine. Some dosage forms listed on this page may not apply to the brand name 12 Hour Cold.

Applies to dexbrompheniramine / pseudoephedrine: oral liquid, oral tablet, oral tablet extended release.

Do not use this medicine if you have used an MAO inhibitor in the past 14 days, such as isocarboxazid, linezolid, methylene blue injection, phenelzine, rasagiline, selegiline, or tranylcypromine.

You should not use antihistamine medication to make a child sleepy.

Get emergency medical help if you have signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Stop using this medicine and call your doctor at once if you have:

  • severe nervousness;

  • a light-headed feeling, like you might pass out;

  • trouble sleeping;

  • fast or uneven heart rate; or

  • painful or difficult urination.

Side effects may be more likely in older adults.

Common side effects may include:

  • drowsiness;

  • feeling restless or excited (especially in children);

  • blurred vision; or

  • dry nose or mouth.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800 FDA 1088.

More about 12 Hour Cold (dexbrompheniramine / pseudoephedrine)

Patient resources

Other brands

Conex, Drixoral Cold and Allergy, Dixaphedrine

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Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.