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Phenylephrine/ guaifenesin/ codeine/ acetaminophen

Generic Name: phenylephrine/guaifenesin/codeine/acetaminophen (FEN-il-EF-rin/gwye-FEN-e-sin/KOE-deen/a-SEET-a-MIN-oh-fen)
Brand Name: Phenflu CDX

Some children have had serious and sometimes fatal breathing problems when using codeine after surgery to remove tonsils or adenoids. Talk with your doctor for more information.

Phenylephrine/ guaifenesin/ codeine/ acetaminophen is used for:

Relieving congestion, cough, pain, and fever due to colds, flu, or allergies. It may also be used for other conditions as determined by your doctor.

Phenylephrine/guaifenesin/codeine/acetaminophen is a decongestant, expectorant, narcotic cough suppressant, and analgesic combination. It works by constricting blood vessels and reducing swelling in the nasal passages, loosening mucus and lung secretions in the chest, and making coughs more productive. The cough suppressant works in the brain to help decrease the cough reflex to reduce a dry cough. The analgesic helps to relieve minor aches and pain and to reduce fever.

Do NOT use phenylephrine/ guaifenesin/ codeine/ acetaminophen if:

  • you are allergic to any ingredient in phenylephrine/guaifenesin/codeine/acetaminophen or any other codeine- or morphine-related medicine (eg, oxycodone)
  • you have severe high blood pressure, an enlarged prostate, or severe heart blood vessel disease
  • you have severe lung or breathing problems or you are having an asthma attack
  • you are taking droxidopa, sodium oxybate (GHB), furazolidone, or a monoamine oxidase inhibitor (MAOI) (eg, phenelzine), or you have taken furazolidone or a MAOI (eg, phenelzine) within the last 14 days
  • the patient is a child and has just had surgery to remove tonsils or adenoids

Contact your doctor or health care provider right away if any of these apply to you.

Before using phenylephrine/ guaifenesin/ codeine/ acetaminophen:

Some medical conditions may interact with phenylephrine/guaifenesin/codeine/acetaminophen. Tell your doctor or pharmacist if you have any medical conditions, especially if any of the following apply to you:

  • if you are pregnant, planning to become pregnant, or are breast-feeding
  • if you are taking any prescription or nonprescription medicine, herbal preparation, or dietary supplement
  • if you have allergies to medicines, foods, or other substances
  • if you have had a severe allergic reaction (eg, severe rash, hives, difficulty breathing, dizziness) to morphine, codeine, or any other opiate (eg, dihydrocodeine, hydrocodone, oxycodone)
  • if you have a history of glaucoma or increased pressure in the eye; an enlarged prostate gland or other prostate problems; heart problems (eg, cor pulmonale, irregular heartbeat); heart blood vessel problems; diabetes; high blood pressure; blood vessel problems; stroke; kidney problems; liver problems (eg, hepatitis); low blood volume; a blockage of your bladder, stomach, or bowel; adrenal gland problems (eg, Addison disease, pheochromocytoma); or thyroid problems
  • if you have a history of constipation, stomach problems, bowel problems (eg, chronic inflammation or ulceration of the bowel), or gallbladder problems (eg, gallstones), or if you have had recent bladder, stomach, or bowel surgery
  • if you have a history of asthma, chronic cough, lung or breathing problems (eg, chronic bronchitis, emphysema, slow or irregular breathing), or chronic obstructive pulmonary disease (COPD), or if your cough occurs with large amounts of mucus
  • if you have severe drowsiness, recent head or brain injury, brain tumor, increased pressure in the brain, infection of the brain or nervous system, or a seizure disorder (eg, epilepsy), or if you have a history of alcohol abuse, drug abuse, or suicidal thoughts or behavior
  • if you have a fever, are in poor health, or drink more than 3 drinks with alcohol per day
  • if you have taken medicine for high blood pressure or depression within the past 14 days

Some MEDICINES MAY INTERACT with phenylephrine/guaifenesin/codeine/acetaminophen. Tell your health care provider if you are taking any other medicines, especially any of the following:

  • Beta-blockers (eg, propranolol), catechol-O-methyltransferase (COMT) inhibitors (eg, tolcapone), cimetidine, furazolidone, HIV protease inhibitors (eg, ritonavir), indomethacin, MAOIs (eg, phenelzine), or tricyclic antidepressants (eg, amitriptyline) because they may increase the risk of phenylephrine/guaifenesin/codeine/acetaminophen's side effects
  • Digoxin, droxidopa, or sodium oxybate (GHB) because the risk of severe drowsiness, breathing problems, seizures, irregular heartbeat, or heart attack may be increased
  • Naltrexone, quinidine, or rifamycins (eg, rifampin) because they may decrease phenylephrine/guaifenesin/codeine/acetaminophen's effectiveness
  • Anticoagulants (eg, warfarin), bromocriptine, or isoniazid because the risk of their side effects may be increased by phenylephrine/guaifenesin/codeine/acetaminophen
  • Guanadrel, guanethidine, mecamylamine, methyldopa, or reserpine because their effectiveness may be decreased by phenylephrine/guaifenesin/codeine/acetaminophen

This may not be a complete list of all interactions that may occur. Ask your health care provider if phenylephrine/guaifenesin/codeine/acetaminophen may interact with other medicines that you take. Check with your health care provider before you start, stop, or change the dose of any medicine.

How to use phenylephrine/ guaifenesin/ codeine/ acetaminophen:

Use phenylephrine/guaifenesin/codeine/acetaminophen as directed by your doctor. Check the label on the medicine for exact dosing instructions.

  • Take phenylephrine/guaifenesin/codeine/acetaminophen by mouth with or without food.
  • If you miss a dose of phenylephrine/guaifenesin/codeine/acetaminophen, take it as soon as possible. If it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not take 2 doses at once.

Ask your health care provider any questions you may have about how to use phenylephrine/guaifenesin/codeine/acetaminophen.

Important safety information:

  • Phenylephrine/guaifenesin/codeine/acetaminophen may cause dizziness or drowsiness. These effects may be worse if you take it with alcohol or certain medicines. Use phenylephrine/guaifenesin/codeine/acetaminophen with caution. Do not drive or perform other possibly unsafe tasks until you know how you react to it.
  • Do not drink alcohol or use medicines that may cause drowsiness (eg, sleep aids, muscle relaxers) while you are using phenylephrine/guaifenesin/codeine/acetaminophen; it may add to their effects. Ask your pharmacist if you have questions about which medicines may cause drowsiness.
  • Phenylephrine/guaifenesin/codeine/acetaminophen may cause dizziness, lightheadedness, or fainting; alcohol, hot weather, exercise, or fever may increase these effects. To prevent them, sit up or stand slowly, especially in the morning. Sit or lie down at the first sign of any of these effects.
  • Do NOT take more than the recommended dose or use for longer than prescribed without checking with your doctor.
  • Phenylephrine/guaifenesin/codeine/acetaminophen may harm your liver. Your risk may be greater if you drink alcohol while you are using phenylephrine/guaifenesin/codeine/acetaminophen. Talk to your doctor before you take phenylephrine/guaifenesin/codeine/acetaminophen or other fever reducers if you drink more than 3 drinks with alcohol per day.
  • A very bad skin reaction (Stevens-Johnson syndrome/toxic epidermal necrolysis) may happen. It can cause very bad health problems that may not go away and sometimes death. Get medical help right away if you have signs like red, swollen, blistered, or peeling skin (with or without fever); red or irritated eyes; or sores in your mouth, throat, nose, or eyes.
  • Phenylephrine/guaifenesin/codeine/acetaminophen may cause you to become sunburned more easily. Avoid the sun, sunlamps, or tanning booths until you know how you react to phenylephrine/guaifenesin/codeine/acetaminophen. Use a sunscreen or wear protective clothing if you must be outside for more than a short time.
  • Phenylephrine/guaifenesin/codeine/acetaminophen has phenylephrine and acetaminophen in it. Before you start any new medicine, check the label to see if it has phenylephrine or acetaminophen in it too. If it does or if you are not sure, check with your doctor or pharmacist.
  • Do not take appetite suppressants while you are taking phenylephrine/guaifenesin/codeine/acetaminophen without checking with your doctor.
  • If your cough or other symptoms persist for more than 1 week, come back, or if you also have fever, rash, or persistent headache, check with your doctor.
  • Phenylephrine/guaifenesin/codeine/acetaminophen may interfere with certain lab tests. Be sure your doctor and lab personnel know you are taking phenylephrine/guaifenesin/codeine/acetaminophen.
  • Tell your doctor or dentist that you take phenylephrine/guaifenesin/codeine/acetaminophen before you receive any medical or dental care, emergency care, or surgery.
  • Use phenylephrine/guaifenesin/codeine/acetaminophen with caution in the ELDERLY; they may be more sensitive to its effects.
  • Phenylephrine/guaifenesin/codeine/acetaminophen should not be used in CHILDREN younger than 6 years old; safety and effectiveness in these children have not been confirmed.
  • PREGNANCY and BREAST-FEEDING: If you become pregnant, contact your doctor. You will need to discuss the benefits and risks of using phenylephrine/guaifenesin/codeine/acetaminophen while you are pregnant. Phenylephrine/guaifenesin/codeine/acetaminophen is found in breast milk. Do not breast-feed while taking phenylephrine/guaifenesin/codeine/acetaminophen.

Possible side effects of phenylephrine/ guaifenesin/ codeine/ acetaminophen:

All medicines may cause side effects, but many people have no, or minor side effects. Check with your doctor if any of these most COMMON side effects persist or become bothersome:

Dizziness; drowsiness; excitability; headache; lightheadedness; nausea; nervousness; trouble sleeping; weakness.

Seek medical attention right away if any of these SEVERE side effects occur:

Severe allergic reactions (rash; hives; itching; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue); confusion; difficulty urinating; fast or irregular heartbeat; hallucinations; involuntary muscle movement; mood or mental changes; seizures; severe dizziness, lightheadedness, or headache; severe drowsiness; slow or irregular breathing; tremor.

This is not a complete list of all side effects that may occur. If you have questions about side effects, contact your health care provider. Call your doctor for medical advice about side effects. To report side effects to the appropriate agency, please read the Guide to Reporting Problems to FDA.

If OVERDOSE is suspected:

Contact 1-800-222-1222 (the American Association of Poison Control Centers), your local poison control center, or emergency room immediately. Symptoms may include confusion; hallucinations; increased sweating; seizures; severe dizziness, lightheadedness, or headache; severe drowsiness; severe or persistent nausea and vomiting; unusually fast, slow, or irregular heartbeat; tremor.

Proper storage of phenylephrine/guaifenesin/codeine/acetaminophen:

Store phenylephrine/guaifenesin/codeine/acetaminophen at room temperature, between 59 and 86 degrees F (15 and 30 degrees C). Store away from heat, moisture, and light. Do not store in the bathroom. Keep phenylephrine/guaifenesin/codeine/acetaminophen out of the reach of children and away from pets.

General information:

  • If you have any questions about phenylephrine/guaifenesin/codeine/acetaminophen, please talk with your doctor, pharmacist, or other health care provider.
  • Phenylephrine/guaifenesin/codeine/acetaminophen is to be used only by the patient for whom it is prescribed. Do not share it with other people.
  • If your symptoms do not improve or if they become worse, check with your doctor.
  • Check with your pharmacist about how to dispose of unused medicine.

This information should not be used to decide whether or not to take phenylephrine/guaifenesin/codeine/acetaminophen or any other medicine. Only your health care provider has the knowledge and training to decide which medicines are right for you. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about phenylephrine/guaifenesin/codeine/acetaminophen. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to phenylephrine/guaifenesin/codeine/acetaminophen. This information is not specific medical advice and does not replace information you receive from your health care provider. You must talk with your healthcare provider for complete information about the risks and benefits of using phenylephrine/guaifenesin/codeine/acetaminophen.

Issue Date: June 3, 2015

Further information

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