- What is guaifenesin, phenylephrine, and how does it work (mechanism of action)?
- What brand names are available for guaifenesin, phenylephrine?
- Is guaifenesin, phenylephrine available as a generic drug?
- Do I need a prescription for guaifenesin, phenylephrine?
- What are the side effects of guaifenesin, phenylephrine?
- What is the dosage for guaifenesin, phenylephrine?
- Which drugs or supplements interact with guaifenesin, phenylephrine?
- Is guaifenesin, phenylephrine safe to take if I'm pregnant or breastfeeding?
- What else should I know about guaifenesin, phenylephrine?
What is guaifenesin, phenylephrine, and how does it work (mechanism of action)?
Guaifenesin/phenylephrine is a medication that contains two different drugs, an expectorant (guaifenesin) and a decongestant (phenylephrine). The expectorant effects of guaifenesin promote drainage of mucus from the lungs by thinning the mucus. It also lubricates the irritated respiratory tract. Phenylephrine relieves stuffy nose by constricting blood vessels in the nasal air passages. This reduces the flow of fluid out of the blood vessels and into the tissues of the air passages.
What brand names are available for guaifenesin, phenylephrine?
Sudafed PE Non-Drying Sinus Caplets, (Entex, discontinued)
What are the side effects of guaifenesin, phenylephrine?
Side effects of guaifenesin/phenylephrine and include stimulation of the nervous system leading to nervousness, restlessness, excitability, dizziness, headache, fear, anxiety, tremor, and even hallucinations and convulsions (seizures). Nausea, vomiting, and rash also occur.
What is the dosage for guaifenesin, phenylephrine?
Guaifenesin/phenylephrine may be taken with or without food. It must be used cautiously in patients with heart (coronary artery) disease and angina, and diabetes.
Which drugs or supplements interact with guaifenesin, phenylephrine?
Guaifenesin/phenylephrine should not be taken with MAO inhibitors drugs due to the increased risk of serious adverse effects

SLIDESHOW
A Cold or The Flu? How to Tell the Difference See SlideshowIs guaifenesin, phenylephrine safe to take if I'm pregnant or breastfeeding?
Phenylephrine can cause birth defects in some animal species. Additionally, there have been associations between first trimester exposure to these medications and malformations, primarily minor malformations. Although one analysis found a correlation between guaifenesin use in the first trimester of pregnancy and an increased risk of hernia, others found no increased risk of malformations. Thus, guaifenesin/phenylephrine should be used in pregnancy only if the physician feels that the potential benefits outweigh the potential risks.
Small amounts of phenylephrine is excreted in breast milk.
What else should I know about guaifenesin, phenylephrine?
What preparations of guaifenesin, phenylephrine are available?
Caplet: 5 mg/200 mg
How should I keep guaifenesin, phenylephrine stored?
Store at room temperature below 30 C (86 F).
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Summary
Guaifenesin and phenylephrine (Sudafed PE Non-Drying Sinus Caplets, (Entex, discontinued) is a drug is prescribed for the relief of sneezing, nasal congestion from the common cold, runny nose, sinusitis, sore throat, or bronchitis. Side effects, drug interactions, dosage, and pregnancy safety information should be reviewed prior to taking this medication.
Related Disease Conditions
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Cough: 19 Tips on How to Stop a Cough
Coughing is a reflex that helps a person clear their airways of irritants. There are many causes of an excessive or severe cough including irritants like cigarette and secondhand smoke, pollution, air fresheners, medications like beta blockers and ACE inhibitors, the common cold, GERD, lung cancer, and heart disease.Natural and home remedies to help cure and soothe a cough include staying hydrated, gargle salt water, use cough drops or lozenges, use herbs and supplements like ginger, mint, licorice, and slippery elm, and don't smoke. Over-the-counter products (OTC)to cure and soothe a cough include cough suppressants and expectorants, and anti-reflux drugs. Prescription drugs that help cure a cough include narcotic medications, antibiotics, inhaled steroids, and anti-reflux drugs like proton pump inhibitors or PPIs, for example, omeprazole (Prilosec), rabeprazole (Aciphex), and pantoprazole (Protonix).
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What Is Mucus?
Mucus is a normal substance produced by lining tissues in the body. Excess mucus or mucus that is yellow, green, brown, or bloody may indicate a problem. Mucus production may increase when allergies, a cold, flu, cough, or sore throat are present. Antihistamines and cold and flu medications may help alleviate excess mucus. A neti pot may be used to decrease nasal congestion and clear mucus.
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Sinus Infection (Sinusitis)
Sinus infection (sinusitis) is caused by allergies, infection, and chemicals or other irritants of sinuses. Signs and symptoms include headache, fever, and facial tenderness, pressure, or pain. Treatments of sinus infections are generally with antibiotics and at times, home remedies.
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Common Cold
The common cold (viral upper respiratory tract infection) is a contagious illness that may be caused by various viruses. Symptoms include a stuffy nose, headache, cough, sore throat, and maybe a fever. Antibiotics have no effect upon the common cold, and there is no evidence that zinc and vitamin C are effective treatments.
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Sore Throat
Sore throat (throat pain) usually is described as pain or discomfort in the throat area. A sore throat may be caused by bacterial infections, viral infections, toxins, irritants, trauma, or injury to the throat area. Common symptoms of a sore throat include a fever, cough, runny nose, hoarseness, earaches, sneezing, and body aches. Home remedies for a sore throat include warm soothing liquids and throat lozenges. OTC remedies for a sore throat include OTC pain relievers such as ibuprofen or acetaminophen. Antibiotics may be necessary for some cases of sore throat.
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Pneumonia
Pneumonia is inflammation of the lungs caused by fungi, bacteria, or viruses. Symptoms and signs include cough, fever, shortness of breath, and chills. Antibiotics treat pneumonia, and the choice of the antibiotic depends upon the cause of the infection.
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Acute Bronchitis
Bronchitis is inflammation of the airways in the lung. Acute bronchitis is short in duration (10-20 days) in comparison with chronic bronchitis, which lasts for months to years. Causes of acute bronchitis include viruses and bacteria, which means it can be contagious. Acute bronchitis caused by environmental factors such as pollution or cigarette smoke is not contagious. Common symptoms for acute bronchitis include nasal congestion, cough, headache, sore throat, muscle aches, and fatigue. Acute bronchitis in children also my include runny nose, fever, and chest pain. Treatment for acute bronchitis are OTC pain relievers, cough suppressants (although not recommended in children), and rest. Infrequently antibiotics may be prescribed to treat acute bronchitis.
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Chronic Bronchitis
Chronic bronchitis is a cough that occurs daily with production of sputum that lasts for at least 3 months, 2 years in a row. Causes of chronic bronchitis include cigarette smoking, inhaled irritants, and underlying disease processes (such as asthma, or congestive heart failure). Symptoms include cough, shortness of breath, and wheezing. Treatments include bronchodilators and steroids. Complications of chronic bronchitis include COPD and emphysema.
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Cold, Flu, Allergy Treatments
Before treating a cold, the flu, or allergies with over-the-counter (OTC) medications, it's important to know what's causing the symptoms, which symptoms one wishes to relieve, and the active ingredients in the OTC product. Taking products that only contain the medications needed for relieving your symptoms prevents ingestion of unnecessary medications and reduces the chances of side effects.
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Sinus Infection vs. Allergies
Both sinus infections and allergies (allergic rhinitis) cause symptoms such as runny or stuffy nose and fatigue. Sinus infection (known as sinusitis) is inflammation of the sinuses, caused by infection from bacteria, viruses, and/or fungi (molds). Allergic rhinitis occurs when certain allergies cause nasal symptoms. When a person with allergies breathes in an allergen, such as pollen, dust, or animal dander, symptoms such as runny or stuffy nose, itching, sneezing, and fatigue occur.
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Can Hot Weather Cause Sinus Problems?
Sinusitis is a condition where you experience irritation and swelling of your sinuses. Allergies and sinus problems are common during the warmer seasons.
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How to Get Rid of a Sinus Infection Fast
The sinuses are air-filled cavities that surround the nose and drain into the nose. They are present in the forehead, the cheeks and near the eyes. Treatment for sinus infections includes over-the-counter pain relievers, decongestants, antibiotics, humidifiers, nasal irrigation, steam inhalation, rest, hydration and warm compresses.
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Report Problems to the Food and Drug Administration
You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.
Reference: FDA Prescribing Information