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Codeine/ guaifenesin/ phenylephrine liquid

Generic name: codeine/guaifenesin/phenylephrine [ KOE-deen/gwye-FEN-e-sin/fen-ill-EF-rin ]
Brand name: Giltuss Ped-C and Tridal

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.


Codeine/ guaifenesin/ phenylephrine liquid is used for:

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

Codeine/guaifenesin/phenylephrine liquid is a decongestant, cough suppressant, and expectorant 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.

Do NOT use codeine/ guaifenesin/ phenylephrine liquid if:

  • you are allergic to any ingredient in codeine/guaifenesin/phenylephrine liquid or any other codeine or morphine related medicine (eg, oxycodone)
  • you have severe high blood pressure, rapid heartbeat, or other severe heart problems (eg, heart blood vessel disease)
  • you are taking sodium oxybate (GHB) or you have taken furazolidone or a monoamine oxidase (MAO) inhibitor (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 codeine/ guaifenesin/ phenylephrine liquid:

Some medical conditions may interact with codeine/guaifenesin/phenylephrine liquid. 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, hydrocodone, dihydrocodeine, oxycodone)
  • if you have a history of glaucoma, an enlarged prostate gland or other prostate problems, heart problems, diabetes, high blood pressure, blood vessel problems, stroke, kidney or liver problems, a blockage of your bowel or bladder, adrenal gland problems (eg, Addison disease), or an underactive thyroid
  • if you have a history of stomach problems, bowel problems (eg, chronic inflammation or ulceration of the bowel), or gallbladder problems (eg, gallstones), or if you have had recent abdominal surgery
  • if you have a history of asthma, chronic cough, lung problems (eg, chronic bronchitis, emphysema), or chronic obstructive pulmonary disease (COPD), or if your cough occurs with large amounts of mucus
  • if you have recently had any head injury, brain injury or tumor, increased pressure in the brain, infection of the brain or nervous system, epilepsy, or seizures
  • if you have a history of alcohol abuse, drug abuse, or suicidal thoughts or behavior

Some MEDICINES MAY INTERACT with codeine/guaifenesin/phenylephrine liquid. 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, MAO inhibitors (eg, phenelzine), or tricyclic antidepressants (eg, amitriptyline) because the risk of side effects from codeine/guaifenesin/phenylephrine liquid may be increased
  • Digoxin, droxidopa, or sodium oxybate (GHB) because the risk of severe drowsiness, breathing problems, seizures, irregular heartbeat, or heart attack may be increased
  • Naltrexone and quinidine because the effectiveness of codeine/guaifenesin/phenylephrine liquid may be decreased.
  • Bromocriptine because the risk of side effects may be increased by codeine/guaifenesin/phenylephrine liquid
  • Guanadrel, guanethidine, mecamylamine, methyldopa, or reserpine because effectiveness may be decreased by codeine/guaifenesin/phenylephrine liquid

This may not be a complete list of all interactions that may occur. Ask your health care provider if codeine/guaifenesin/phenylephrine liquid 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 codeine/ guaifenesin/ phenylephrine liquid:

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

  • Take codeine/guaifenesin/phenylephrine liquid by mouth with or without food.
  • Drink plenty of water while taking codeine/guaifenesin/phenylephrine liquid.
  • Use a measuring device marked for medicine dosing. Ask your pharmacist for help if you are unsure of how to measure your dose.
  • If you miss a dose of codeine/guaifenesin/phenylephrine liquid, 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 codeine/guaifenesin/phenylephrine liquid.

Important safety information:

  • Codeine/guaifenesin/phenylephrine liquid may cause dizziness or drowsiness. These effects may be worse if you take it with alcohol or certain medicines. Use codeine/guaifenesin/phenylephrine liquid with caution. Do not drive or perform other possibly unsafe tasks until you know how you react to it.
  • Do not take appetite suppressants while you are taking codeine/guaifenesin/phenylephrine liquid without checking with your doctor.
  • Codeine/guaifenesin/phenylephrine liquid has phenylephrine in it. Before you start any new medicine, check the label to see if it has phenylephrine in it too. If it does or if you are not sure, check with your doctor or pharmacist.
  • Do NOT take more than the recommended dose or use for longer than prescribed without checking with your doctor.
  • If your symptoms do not get better within 5 to 7 days or if they get worse, check with your doctor.
  • Codeine/guaifenesin/phenylephrine liquid may interfere with certain lab tests. Be sure your doctor and lab personnel know you are taking codeine/guaifenesin/phenylephrine liquid.
  • Tell your doctor or dentist that you take codeine/guaifenesin/phenylephrine liquid before you receive any medical or dental care, emergency care, or surgery.
  • Use codeine/guaifenesin/phenylephrine liquid with caution in the ELDERLY; they may be more sensitive to its effects.
  • Caution is advised when using codeine/guaifenesin/phenylephrine liquid in CHILDREN; they may be more sensitive to its effects.
  • PREGNANCY and BREAST-FEEDING: If you become pregnant, contact your doctor. You will need to discuss the benefits and risks of using codeine/guaifenesin/phenylephrine liquid while you are pregnant. It is not known if this medicine is found in breast milk. Do not breast-feed while taking codeine/guaifenesin/phenylephrine liquid.

Possible side effects of codeine/ guaifenesin/ phenylephrine liquid:

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; nausea; nervousness or anxiety; 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); difficulty urinating; fast or irregular heartbeat; hallucinations; seizures; severe dizziness, lightheadedness, or headache; severe drowsiness; 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 blurred vision; confusion; hallucinations; seizures; severe dizziness, lightheadedness, or headache; severe drowsiness; unusually fast, slow, or irregular heartbeat; vomiting.

Proper storage of codeine/guaifenesin/phenylephrine liquid:

Store codeine/guaifenesin/phenylephrine liquid 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 codeine/guaifenesin/phenylephrine liquid out of the reach of children and away from pets.

General information:

  • If you have any questions about codeine/guaifenesin/phenylephrine liquid, please talk with your doctor, pharmacist, or other health care provider.
  • Codeine/guaifenesin/phenylephrine liquid 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 codeine/guaifenesin/phenylephrine liquid 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 codeine/guaifenesin/phenylephrine liquid. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to codeine/guaifenesin/phenylephrine liquid. 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 codeine/guaifenesin/phenylephrine liquid.

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.