What is Dextromethorphan, guaifenesin,and phenylephrine?
Dextromethorphan suppresses coughing by affecting brain signals that trigger the cough reflex. Guaifenesin loosens up congestion in the chest and throat. Phenylephrine shrinks the blood vessels in the nasal passages. Combination medicine that contains dextromethorphan with guaifenesin and phenylephrine treats cough, congestion, and stuffy nose caused by allergies or flu. Dextromethorphan is not effective in treating a cough caused by asthma or emphysema, nor will it treat a cough due to smoking. This medicine is available in many different brands and forms. This leaflet does not list all brands. This medication guide does not list all possible uses for dextromethorphan.
Side Effects of Dextromethorphan, guaifenesin,and phenylephrine
In case of an allergic reaction, seek medical help immediately if any of these symptoms arise: difficulty breathing, hives or swelling to lips, face or throat.
This medicine can cause serious side effects. If you experience:
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Little or no urination
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Fast or slow heartbeats
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Confusion, dizziness, feeling unsteady;
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Nervousness; sleep problems (insomnia);
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Severe nausea or vomiting;
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An intense headache may cause blurry vision or cause pain to radiate throughout your neck and ears, even to your brain itself.
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Slow breathing
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Unusual changes in mood or behavior
Some of the common side effects that may occur from dextromethorphan and other drugs such as guaifenesin or phenylephrine include:
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Diarrhea, constipation;
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Dizziness, drowsiness;
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Sleep problems (insomnia);
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Feeling nervous, restless, or irritable.
There may be other side effects.Call your physician if experiencing side effects; for reporting purposes call the FDA directly at 1-800-FDA-1088.
Warnings
This medicine should not be used if you've taken MAO inhibitors in the last 14 days.These include isocarboxazid (linezolid), phenelzine, rasagiline and tranylcypromine.
Before you take this drug
This medicine should not be used if you have an allergy to dextromethorphan or phenylephrine. You should not take this medication if you've taken an MAO inhibitor in the last 14 days. It is possible that a dangerous drug interaction will occur. MAO inhibitors include isocarboxazid (Linezolid), phenelzine (Rasagiline), Selegiline (Tranylcypromine), and Rasagiline.
If you suffer from:
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Heart disease, high blood pressure
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Diabetes;
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A thyroid disorder
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Urination problems
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Glaucoma;
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Epilepsy or another seizure disorder
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Pheochromocytoma
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Chronic bronchitis or emphysema can cause a cough that is mucus-laden.
This medication may contain phenylalanine. If you have phenylketonuria, check the label of your medication. Consult your doctor before taking this medication if you're pregnant or breastfeeding.
How to take Dextromethorphan, guaifenesin,and phenylephrine?
Follow the directions provided on the label or prescribed by your physician when taking cold and cough medicines for temporary relief only, taking them according to label directions when giving these treatments to children and never in an effort to put them to sleep. Do not crush, chew or break tablets prior to swallowing! Always swallow all parts of a tablet as intended. Dosage measurement of liquid medicine should always be conducted accurately. Use either the provided dosing device or another dose-measuring tool (never spoon!) when taking medicine orally. Drink plenty of fluids while taking this medication in order to ease congestion and protect the throat from irritation. This may help loosen and smoothen lubrication while relieving discomfort in your throat. If your symptoms do not improve within seven days or if they worsen with fever or headache symptoms, please visit a medical provider as soon as possible. Tell your doctor or surgeon, if you have taken medication in the last several days and will require medical tests or surgery. Store at room temperature away from moisture or heat to maintain optimal storage conditions. Liquid medicines should not be allowed to freeze.
What happens if I miss the dose?
Cough and cold medications shouldn't be taken on an established schedule - take them when needed as needed! When it is almost time for your next dose, skip any missed one; never double up on doses at one sitting.
What happens if I overdose?
Call 1-800-222-1222 for poison help or seek immediate medical attention.
What should be avoided?
Do not drive or engage in hazardous activities until you have determined how the medicine will affect you. You may be unable to react properly. Certain side effects can be exacerbated by alcohol consumption. Before purchasing alternative cold and cough remedies, always consult a healthcare provider or pharmacist about whether their ingredients contain similar substances.
Interaction with other drug
Avoid taking dextromethorphan with other drugs that cause drowsiness, such as muscle relaxers, opioids, or medicines for anxiety or seizures. Before taking any other medications, such as herbal products, prescription medicines, or over-the-counter medicines, ask your doctor or pharmacist. This medication guide does not list all possible interactions with other drugs.
