codeine, guaifenesin, and phenylephrine

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Pronunciation: KOE deen, gwye FEN e sin, FEN il EFF rin

Brand: Maxiphen CD, Maxiphen CDX

What is the most important information I should know about this medicine?

Do not use this medicine if you have used an MAO inhibitor in the past 14 days, such as isocarboxazid, linezolid, methylene blue injection, phenelzine, rasagiline, selegiline, or tranylcypromine.

Codeine can slow or stop your breathing. Never use this medicine in larger amounts, or for longer than prescribed. Codeine may also be habit-forming. Never share this medicine with another person. MISUSE OF NARCOTIC MEDICINE CAN CAUSE ADDICTION, OVERDOSE, OR DEATH.

Medicines that contain codeine should not be given to a child just after surgery to remove the tonsils or adenoids. Get emergency medical help if a child taking this medicine has breathing problems, blue lips, or severe drowsiness, or if you cannot wake the child up from sleep.

What is codeine, guaifenesin, and phenylephrine?

Codeine is a narcotic 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).

Codeine, guaifenesin, and phenylephrine is a combination medicine used to treat stuffy nose, cough, sinus congestion, and chest congestion caused by allergies, the common cold, or the flu.

This medicine will not treat a cough that is caused by smoking, asthma, or emphysema.

Codeine, guaifenesin, and phenylephrine may also be used for purposes not listed in this medication guide.

What should I discuss with my healthcare provider before taking this medicine?

Do not use this medicine if you have used an MAO inhibitor in the past 14 days. A dangerous drug interaction could occur. MAO inhibitors include isocarboxazid, linezolid, methylene blue injection, phenelzine, rasagiline, selegiline, tranylcypromine, and others.

Always ask a doctor before giving codeine, guaifenesin, and phenylephrine to a child. Death can occur from the misuse of cough and cold medicines in very young children. Medicines that contain codeine should not be given to a child just after surgery to remove the tonsils or adenoids.

In some people, codeine breaks down rapidly in the liver and reaches higher than normal levels in the body. This can cause dangerously slow breathing and may cause death, especially in a child.

To make sure codeine, guaifenesin, and phenylephrine is safe for you, tell your doctor if you have:

  • heart disease or high blood pressure;
  • diabetes;
  • a thyroid disorder;
  • liver or kidney disease;
  • a cough with mucus;
  • asthma, COPD, or other breathing disorder;
  • blockage in your digestive tract (stomach or intestines);
  • low blood pressure;
  • a history of drug or alcohol addiction;
  • a history of head injury or brain tumor; or
  • if you have been sick with diarrhea.

It is not known whether this medicine will harm an unborn baby. If you use codeine while you are pregnant, your baby could become dependent on the drug. This can cause life-threatening withdrawal symptoms in the baby after it is born. Babies born dependent on habit-forming medicine may need medical treatment for several weeks. Tell your doctor if you are pregnant or plan to become pregnant.

Codeine can pass into breast milk and may harm a nursing baby. The use of codeine by some nursing mothers may lead to life-threatening side effects in the baby. Do not use this medicine without telling your doctor if you are breast-feeding a baby.

How should I take this medicine?

Follow all directions on your prescription label. Codeine can slow or stop your breathing. Never use codeine, guaifenesin, and phenylephrine in larger amounts, or for longer than prescribed. Cough or cold medicine is usually taken only for a short time until your symptoms clear up.

Codeine may be habit-forming, even at regular doses. Never share this medicine with another person, especially someone with a history of drug abuse or addiction. MISUSE OF NARCOTIC MEDICINE CAN CAUSE ADDICTION, OVERDOSE, OR DEATH, especially in a child or other person using the medicine without a prescription. Selling or giving away codeine is against the law.

Drink extra fluids to help loosen the congestion and lubricate your throat while you are taking this medicine.

Call your doctor if your symptoms do not improve after 7 days of treatment, or if you have a fever with a headache or skin rash.

If you need surgery or medical tests, tell the surgeon or doctor ahead of time if you have taken a cough or cold medicine within the past few days.

Store at room temperature away from moisture and heat. Keep track of the amount of medicine used from each new bottle. Codeine is a drug of abuse and you should be aware if anyone is using your medicine improperly or without a prescription.

What happens if I miss a dose?

Since this medicine is taken when needed, you may not be on a dosing schedule. If you are taking the medication regularly, take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222. A codeine overdose can be fatal, especially in a child or other person using the medicine without a prescription. Overdose symptoms may include slow breathing and heart rate, severe drowsiness, muscle weakness, cold and clammy skin, pinpoint pupils, and fainting.

What should I avoid while taking this medicine?

This medicine may impair your thinking or reactions. Avoid driving or operating machinery until you know how this medicine will affect you. Dizziness or severe drowsiness can cause falls or other accidents.

Do not drink alcohol while you are taking medicine that contains codeine. Dangerous side effects or death can occur when alcohol is combined with a narcotic medicine.

Ask a doctor or pharmacist before using any other cold or cough medicine. Many combination medicines contain guaifenesin or phenylephrine. Taking certain products together can cause you to get too much of this medicine. Check the label to see if a medicine contains a decongestant or an expectorant.

What are the possible side effects of this medicine?

Get emergency medical help if you have signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Stop taking this medicine and call your doctor at once if you have:

  • painful or difficult urination;
  • fast or uneven heart rate;
  • weak or shallow breathing;
  • severe dizziness or drowsiness, feeling like you might pass out;
  • tremors or seizure (convulsions);
  • confusion, hallucinations; or
  • dangerously high blood pressure (severe headache, blurred vision, pounding in your neck or ears, nosebleed, anxiety).

Older adults may be more sensitive to the effects of this medicine.

Common side effects may include:

  • feeling nervous, anxious, or excited;
  • dizziness, drowsiness;
  • weakness;
  • sleep problems (insomnia);
  • headache; or
  • nausea.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What other drugs will affect this medicine?

Taking this medicine with other drugs that make you sleepy or slow your breathing can cause dangerous or life-threatening side effects. Ask your doctor before taking codeine, guaifenesin, and phenylephrine with a sleeping pill, narcotic pain medicine, muscle relaxer, or medicine for anxiety, depression, or seizures.

Other drugs may interact with codeine, guaifenesin, and phenylephrine, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell each of your health care providers about all medicines you use now and any medicine you start or stop using.

Where can I get more information?

Your pharmacist can provide more information about codeine, guaifenesin, and phenylephrine.


Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

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