Generic Name: codeine, guaifenesin, and phenylephrine (KOE deen, gwye FEN e sin, FEN il EFF rin)
Brand Names: Maxiphen CD, Maxiphen CDX
What is Maxiphen CDX (codeine, guaifenesin, and phenylephrine)?
Codeine is in a group of drugs called narcotics. It is a cough suppressant that affects the signals in the brain that trigger cough reflex.
Guaifenesin is an expectorant. It helps loosen mucus 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).
The combination of codeine, guaifenesin, and phenylephrine is used to treat cough, nasal, and sinus congestion, and to reduce chest congestion caused by upper respiratory infections or the common cold.
Codeine, guaifenesin, and phenylephrine may also be used for purposes other than those listed in this medication guide.
What is the most important information I should know about Maxiphen CDX (codeine, guaifenesin, and phenylephrine)?
Do not take this medication if you have used an MAO inhibitor such as isocarboxazid (Marplan), phenelzine (Nardil), rasagiline (Azilect), selegiline (Eldepryl, Emsam), or tranylcypromine (Parnate) within the past 14 days. Serious, life-threatening side effects can occur if you take cough or cold medicine before the MAO inhibitor has cleared from your body. Do not use any other over-the-counter cough or cold medication without first asking your doctor or pharmacist. If you take certain products together you may accidentally take too much of one or more types of medicine. Read the label of any other medicine you are using to see if it contains guaifenesin or phenylephrine. Codeine may be habit-forming and should be used only by the person it was prescribed for. This medication should never be shared with another person, especially someone who has a history of drug abuse or addiction. Keep the medication in a secure place where others cannot get to it. Always ask a doctor before giving a cough or cold medicine to a child. Death can occur from the misuse of cough and cold medicines in very young children.
What should I discuss with my healthcare provider before taking Maxiphen CDX (codeine, guaifenesin, and phenylephrine)?
Do not take this medication if you have used an MAO inhibitor such as isocarboxazid (Marplan), phenelzine (Nardil), rasagiline (Azilect), selegiline (Eldepryl, Emsam), or tranylcypromine (Parnate) within the past 14 days. Serious, life-threatening side effects can occur if you take cough or cold medicine before the MAO inhibitor has cleared from your body. You should not take codeine, guaifenesin, and phenylephrine if you have ever had an allergic reaction to it, or if you have:
severe or uncontrolled high blood pressure;
severe coronary artery disease;
enlarged prostate; or
if you are breast-feeding a baby.
If you have certain conditions, you may need a dose adjustment or special tests to safely take codeine, guaifenesin, and phenylephrine. Before taking this medication, tell your doctor if you are allergic to any drugs, or if you have:
heart disease or high blood pressure;
ischemic heart disease (reduced circulation of blood to the heart);
asthma, COPD, sleep apnea, or other breathing disorders;
diabetes;
a thyroid disorder;
glaucoma;
a history of head injury or brain tumor;
epilepsy or other seizure disorder;
- liver or kidney disease;
a stomach or intestinal disorder;
Addison's disease or other adrenal gland disorders; or
if you have recently had stomach, bladder, or kidney surgery.
FDA pregnancy category C. This medication may be harmful to an unborn baby, and could cause addiction or withdrawal symptoms in a newborn. Tell your doctor if you are pregnant or plan to become pregnant during treatment. 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 medication if you are breast-feeding a baby. Codeine may be habit-forming and should be used only by the person it was prescribed for. Codeine should never be shared with another person, especially someone who has a history of drug abuse or addiction. Keep the medication in a secure place where others cannot get to it. Codeine is a drug of abuse and you should be aware if any person in the household is using this medicine improperly or without a prescription. Older adults may be more likely to have side effects from this medication.
How should I take Maxiphen CDX (codeine, guaifenesin, and phenylephrine)?
Take this medication exactly as it has been prescribed by your doctor. Do not use the medication in larger amounts, or use it for longer than recommended. Cough or cold medicine is usually taken only for a short time until your symptoms clear up.
Always ask a doctor before giving cough or cold medicine to a child. Death can occur from the misuse of cough or cold medicine in very young children. Take codeine, guaifenesin, and phenylephrine with food if it upsets your stomach. Call your doctor if your symptoms do not improve after 7 days of treatment, or if you also have a fever, headache, or skin rash.
This medication can cause you to have unusual results with certain medical tests. Tell any doctor who treats you that you are using codeine guaifenesin, and phenylephrine.
Store this medicine at room temperature, away from heat, light, and moisture.
Keep track of how many pills have been used from each new bottle of this medicine. Codeine is a drug of abuse and you should be aware if any person in the household is using this medicine improperly or without a prescription.
What happens if I miss a dose?
Since cough or cold medicine is usually taken only as 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. If it is almost time for your next dose, skip the missed dose and take the medicine at your next regularly scheduled time. Do not take extra medicine to make up the missed dose.
What happens if I overdose?
Seek emergency medical attention if you think you have used too much of this medicine. An overdose of codeine can be fatal.
Overdose symptoms may include extreme dizziness or drowsiness, nausea, vomiting, stomach, sweating, confusion, hallucinations, cold and clammy skin, blue-colored lips or fingernails, weak or limp muscles, pinpoint pupils, weak pulse, slow breathing, fainting, or seizures (convulsions).
What should I avoid while taking Maxiphen CDX (codeine, guaifenesin, and phenylephrine)?
This medication can cause side effects that may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be awake and alert.
Do not use any other over-the-counter cough, cold, pain, or allergy medication without first asking your doctor or pharmacist. Guaifenesin and phenylephrine are contained in many medicines available over the counter. If you take certain products together you may accidentally take too much of a certain drug. Read the label of any other medicine you are using to see if it contains guaifenesin or phenylephrine.
Avoid drinking alcohol. It can increase some of the side effects of this medication.
Maxiphen CDX (codeine, guaifenesin, and phenylephrine) side effects
Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat. Stop taking this medication and call your doctor at once if you have any of these serious side effects:
severe dizziness, anxiety, restless feeling, or nervousness, tremors;
confusion, hallucinations, unusual thoughts or behavior;
seizure (convulsions);
fast, pounding, or uneven heartbeat;
slow heart rate, weak pulse, fainting, weak or shallow breathing; or
increased blood pressure (severe headache, blurred vision, trouble concentrating, chest pain, numbness, seizure).
Less serious side effects include:
dizziness, drowsiness, headache;
nausea, vomiting;
constipation;
feeling excited or restless;
sleep problems (insomnia);
warmth, tingling, or redness under your skin; or
skin rash or itching.
This is not a complete list of side effects and others may occur. Tell your doctor about any unusual or bothersome side effect. You may report side effects to FDA at 1-800-FDA-1088.
What other drugs will affect Maxiphen CDX (codeine, guaifenesin, and phenylephrine)?
Before taking this medication, tell your doctor if you regularly use other medicines that make you sleepy (such as allergy medicine, narcotic pain medicine, sleeping pills, muscle relaxers, and medicine for seizures, depression, or anxiety). They can add to sleepiness caused by codeine or guaifenesin.
Also tell your doctor if you are using any of the following drugs:
medicines to treat high blood pressure;
indomethacin (Indocin);
mecamylamine (Inversine);
methyldopa (Aldomet);
reserpine;
a beta-blocker such as atenolol (Tenormin), carteolol (Cartrol), metoprolol (Lopressor, Toprol), nadolol (Corgard), propranolol (Inderal), sotalol (Betapace), timolol, and others; or
an antidepressant such as amitriptyline (Elavil), clomipramine (Anafranil), imipramine (Janimine, Tofranil), and others.
This list is not complete and there may be other drugs that can interact with codeine, guaifenesin, and phenylephrine. Tell your doctor about all the prescription and over-the-counter medications you use. This includes vitamins, minerals, herbal products, and drugs prescribed by other doctors. Do not start using a new medication without telling your doctor.
More Maxiphen CDX resources
- Maxiphen CDX Use in Pregnancy & Breastfeeding
- Maxiphen CDX Drug Interactions
- Maxiphen CDX Support Group
- 0 Reviews for Maxiphen CDX - Add your own review/rating
- Codeine/Guaifenesin/Phenylephrine Liquid MedFacts Consumer Leaflet (Wolters Kluwer)
Compare Maxiphen CDX with other medications
- Cough and Nasal Congestion
Where can I get more information?
- Your pharmacist can provide more information about codeine, guaifenesin, and phenylephrine.
