What is dextromethorphan, guaifenesin, and phenylephrine?
Dextromethorphan is a cough suppressant. It affects the signals in the brain that trigger cough reflex.
Guaifenesin is an expectorant. It helps loosen congestion in your chest and throat, making it easier to cough out through your mouth.
Phenylephrine is a decongestant that shrinks blood vessels in the nasal passages. Dilated blood vessels can cause nasal congestion (stuffy nose).
The combination of dextromethorphan, guaifenesin, and phenylephrine is used to treat stuffy nose, sinus congestion, cough, and chest congestion caused by the common cold or flu.
Dextromethorphan will not treat a cough that is caused by smoking, asthma, or emphysema.
Dextromethorphan, guaifenesin, and phenylephrine may also be used for other purposes not listed in this medication guide.
What is the most important information I should know about dextromethorphan, guaifenesin, and phenylephrine?
Do not give this medication to a child younger than 2 years old. Always ask a doctor before giving a cough or cold medicine to a child. Death can occur from the misuse of cough and cold medicines in very young children.
Do not use a cough or cold medicine if you have used an MAO inhibitor such as isocarboxazid (Marplan), phenelzine (Nardil), rasagiline (Azilect), selegiline (Eldepryl, Emsam), or tranylcypromine (Parnate) within the past 14 days. Serious, life-threatening side effects can occur if you take cough or cold medicine before the MAO inhibitor has cleared from your body.
Do not use any other over-the-counter cough, cold, allergy, or sleep medication without first asking your doctor or pharmacist. If you take certain products together you may accidentally take too much of one or more types of medicine. Read the label of any other medicine you are using to see if it contains a decongestant, expectorant, or cough suppressant.
Dextromethorphan will not treat a cough that is caused by smoking, asthma, or emphysema.
What should I discuss with my healthcare provider before using dextromethorphan, guaifenesin, and phenylephrine?
Do not use a cough or cold medicine if you have used an MAO inhibitor such as isocarboxazid (Marplan), phenelzine (Nardil), rasagiline (Azilect), selegiline (Eldepryl, Emsam), or tranylcypromine (Parnate) within the past 14 days. Serious, life-threatening side effects can occur if you take cough or cold medicine before the MAO inhibitor has cleared from your body.
Do not use this medicine if you are allergic to dextromethorphan, guaifenesin, or phenylephrine.
Ask a doctor or pharmacist if it is safe for you to take this medication if you have emphysema or chronic bronchitis.
This medication may be harmful to an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant during treatment.
This medication may pass into breast milk and could harm a nursing baby. Do not use this medication without telling your doctor if you are breast-feeding a baby.
Artificially-sweetened liquid forms of cold medicine may contain phenylalanine. This would be important to know if you have phenylketonuria (PKU). Check the ingredients and warnings on the medication label if you are concerned about phenylalanine.