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M-Clear
Generic name: codeine and guaifenesin
Brand names: Mar-cof CG, Allfen CD, Cheratussin AC, Codar GF, Duraganidin NR, Guaiatussin AC, Iophen-C NR, M-Clear, Mytussin AC, Relcof C
What is M-Clear?
Codeine is a narcotic cough suppressant. It works on the signals in the brain that cause the cough reflex.
Guaifenesin is an expectorant. It helps to loosen congestion in your chest and throat, making it easier to cough it out through your mouth.
M-Clear is a combination medicine used to treat cough and chest congestion caused by allergies, the common cold, or the flu.
M-Clear will not treat a cough that is caused by smoking, asthma, or emphysema.
M-Clear may also be used for purposes not listed in this medication guide.
This section was rewritten for readability and reviewed for meaning.
How should I take M-Clear?
Follow all directions on your prescription label. Codeine can slow or stop your breathing. Never use M-Clear in larger amounts, or for longer than prescribed. Cough or cold medicine is usually taken only for a short time until your symptoms go away.
Codeine may be habit-forming, even at regular doses. Never share M-Clear 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.
Measure liquid medicine with the dosing syringe provided, or with a special dose-measuring spoon or medicine cup. If you do not have a dose-measuring device, ask your pharmacist for one.
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.
Store at room temperature away from moisture and heat. Do not freeze. 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.
This section was rewritten for readability and reviewed for meaning.
Warnings
Codeine can slow down or stop your breathing and may lead to dependence. MISUSE OF M-Clear CAN CAUSE ADDICTION, OVERDOSE, OR DEATH, particularly in a child or anyone taking the medicine without a prescription.
Do not give this medicine to anyone younger than 18.
This section was rewritten for readability and reviewed for meaning.
Before taking this medicine
You should not take this medicine if you are allergic to codeine or guaifenesin.
In some people, codeine breaks down quickly in the liver and can lead to higher than normal levels in the body. This can cause dangerously slow breathing and may result in death, especially in a child.
Do not give this medicine to anyone under 18.
To ensure M-Clear is safe for you, tell your doctor if you have ever had:
- a cough with mucus;
- asthma, COPD, or another breathing disorder;
- a blockage in your digestive tract (stomach or intestines);
- a head injury or brain tumor;
- low blood pressure; or
- drug or alcohol addiction.
If you use codeine during pregnancy, your baby could become dependent on the drug. This can lead to life-threatening withdrawal symptoms in the baby after birth. Babies born dependent on habit-forming medicine may require medical treatment for several weeks. Tell your doctor if you are pregnant or plan to become pregnant.
Do not breast-feed. Codeine can pass into breast milk and may cause drowsiness, breathing problems, or death in a nursing baby. Do not breast-feed.
This section was rewritten for readability and reviewed for meaning.
M-Clear side effects
Get emergency medical help if you notice signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.
Like other narcotic medications, codeine can slow your breathing. Death may occur if breathing becomes too weak.
A person taking care of you should seek emergency medical attention if you have slow breathing with long pauses, blue lips, or if you are hard to wake up.
This medicine may cause serious side effects. Stop using this medicine and call your doctor right away if you have:
- noisy breathing, sighing, shallow breathing;
- a slow heart rate or weak pulse;
- severe dizziness or drowsiness;
- confusion, hallucinations, unusual thoughts or behavior;
- little or no urination;
- severe constipation; or
- slow heart rate, weak or shallow breathing.
Serious side effects may be more likely in older adults and those who are overweight, malnourished, or weakened.
Common side effects of M-Clear may include:
- constipation; or
- mild drowsiness.
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.
This section was rewritten for readability and reviewed for meaning.
What happens if I miss a dose?
Since M-Clear is taken as needed, you might not have a set dosing schedule. If you do have a schedule, take the missed dose as soon as you remember. If it’s almost time for your next scheduled dose, skip the missed dose. Do not take extra medicine to compensate for the missed dose.
This section was rewritten for readability and reviewed for meaning.
What happens if I overdose?
Seek emergency medical help or call the Poison Help line at 1-800-222-1222. A codeine overdose can be deadly, especially in a child or anyone using the medicine without a prescription. Symptoms of an overdose may include slow breathing and heart rate, severe drowsiness, muscle weakness, cold and clammy skin, pinpoint pupils, and fainting.
M-Clear may affect your thinking or reactions. Avoid driving or using machinery until you know how this medicine affects you. Dizziness or severe drowsiness can lead to falls or other accidents.
Do not drink alcohol. Serious side effects or death could happen.
Ask a doctor or pharmacist before using any other cough or cold medicine. Many combination medicines contain guaifenesin. Taking certain products together can lead to getting too much of this medicine.
This section was rewritten for readability and reviewed for meaning.
What other drugs will affect M-Clear?
Taking M-Clear with other medications that make you sleepy or slow your breathing can lead to serious side effects or death. Talk to your doctor before taking a sleeping pill, narcotic pain medicine, prescription cough medicine, muscle relaxer, or medicine for anxiety, depression, or seizures.
Other medications may interact with codeine and guaifenesin, including both prescription and over-the-counter medicines, vitamins, and herbal products. Inform your doctor about all the medicines you are currently taking and any medicine you start or stop.
This section was rewritten for readability and reviewed for meaning.
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Content is provided for education and is not medical advice. See our medical disclaimer.