Medically reviewed by Drugs.com. Last updated on Jul 4, 2022.
The Codeprex brand name has been discontinued in the U.S. If generic versions of this product have been approved by the FDA, there may be generic equivalents available.
What is Codeprex?
Chlorpheniramine is an antihistamine. It blocks the effects of histamine in the body. Chlorpheniramine prevents sneezing; itchy, watery eyes and nose; and other symptoms of allergies and colds. Codeprex is a combination of chlorpheniramine and codeine.
Codeprex is used to treat nasal congestion and coughs associated with allergies and the common cold.
Codeprex may also be used for purposes other than those listed in this medication guide.
WarningsUse caution when driving, operating machinery, or performing other hazardous activities. Codeprex may cause dizziness or drowsiness. If you experience dizziness or drowsiness, avoid these activities. Use alcohol cautiously. Alcohol may increase drowsiness and dizziness while taking Codeprex.
Do not take more of this medication than is recommended. If your symptoms do not improve, or if they worsen, talk to your doctor.Codeine may be habit forming. Physical and/or psychological dependence can occur, and withdrawal effects are possible if the medication is stopped suddenly after prolonged or high-dose treatment. Do not stop taking Codeprex suddenly without first talking to your doctor if you have been taking it continuously for more than 5 to 7 days. Your doctor may want to gradually reduce the dose.
Before taking this medicineDo not take Codeprex without first talking to your doctor if you have
an allergy to codeine, morphine, or other narcotic medications;
- kidney disease;
- liver disease;
a head injury;
heart disease or high blood pressure;
asthma or lung disease; or
difficulty urinating or have an enlarged prostate.
You may not be able to take Codeprex, or you may require a dosage adjustment or special monitoring during treatment if you have any of the conditions listed above.Codeprex is in the FDA pregnancy category C. This means that it is not known whether it will be harmful to an unborn baby. Do not take Codeprex without first talking to your doctor if you are pregnant or could become pregnant during treatment. It is not known whether Codeprex passes into breast milk. Do not take this medication without first talking to your doctor if you are breast-feeding a baby. If you are over 60 years of age, you may be more likely to experience side effects from Codeprex. Your doctor may prescribe a lower dose of the medication.
How should I take Codeprex?
Take Codeprex exactly as directed. If you do not understand these directions, ask your pharmacist, nurse, or doctor to explain them to you.Shake the liquid form of Codeprex well before measuring a dose. To ensure that you get a correct dose, measure the suspension with a dose-measuring spoon, dropper, or cup, not a regular table spoon. If you do not have a dose-measuring device, ask your pharmacist where you can get one. Do not mix the suspension with any other liquid before taking it. Mixing it with another liquid may change the way the medication is absorbed in the body. Codeprex can be taken with food if stomach upset occurs. Do not take more of this medication than is recommended. An overdose of this medication can cause serious harm. Codeine may be habit forming. Physical and/or psychological dependence can occur, and withdrawal effects are possible if the medication is stopped suddenly after prolonged or high-dose treatment. Do not stop taking Codeprex suddenly without first talking to your doctor if you have been taking it continuously for more than 5 to 7 days. Your doctor may want to gradually reduce the dose. Store Codeprex at room temperature away from moisture and heat.
What happens if I miss a dose?
Take the missed dose as soon as you remember. However, if it is almost time for the next dose, skip the missed dose and take only the next regularly scheduled dose. Do not take a double dose of this medication.
What happens if I overdose?Seek emergency medical attention if an overdose is suspected.
Symptoms of a Codeprex overdose may include severe drowsiness, dizziness, headache, seizures, dry mouth, cold and clammy skin, flushing, large pupils, nausea, vomiting, difficulty or decreased breathing, blue colored skin, and unconsciousness.
What should I avoid?Use caution when driving, operating machinery, or performing other hazardous activities. Codeprex may cause dizziness or drowsiness. If you experience dizziness or drowsiness, avoid these activities. Use alcohol cautiously. Alcohol may increase drowsiness and dizziness while taking Codeprex.
Codeprex side effectsIf you experience any of the following serious side effects, stop taking Codeprex and seek emergency medical attention or contact your doctor immediately:
an allergic reaction (difficulty breathing; closing of the throat; swelling of the lips, tongue, or face; or hives); or
confusion, hallucinations, or unusual behavior.
Other, less serious side effects may be more likely to occur. Continue to take Codeprex and talk to your doctor if you experience
dizziness, drowsiness, or sleepiness;
restlessness or irritability;
dry mouth, nausea, vomiting, or decreased appetite;
Side effects other than those listed here may also occur. Talk to your doctor about any side effect that seems unusual or that is especially bothersome.
What other drugs will affect Codeprex?
Do not take other over-the-counter cough, cold, allergy, diet, or sleep aids while taking Codeprex without first talking to your doctor or pharmacist. Other medications may also contain chlorpheniramine, codeine, or other similar drugs. You may accidentally take too much of these medicines.
Codeprex may increase the effects of other drugs that cause drowsiness, including antidepressants, alcohol, other antihistamines, pain relievers, anxiety medicines, seizure medicines, and muscle relaxants. Dangerous sedation, dizziness, or drowsiness may occur if Codeprex is taken with any of these medications.
Drugs other than those listed here may also interact with Codeprex. Talk to your doctor and pharmacist before taking any prescription or over-the-counter medicines, including herbal products.
Where can I get more information?
- Your pharmacist has additional information about Codeprex written for health professionals that you may read.
What does my medication look like?
Chlorpheniramine and codeine is available with a prescription under the brand name Codeprex. Other brand or generic formulations may also be available. Ask your pharmacist any questions you have about this medication, especially if it is new to you.
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.Copyright 1996-2023 Cerner Multum, Inc. Version: 1.01.
More about Codeprex (chlorpheniramine / codeine)
- Check interactions
- Side effects
- Dosage information
- During pregnancy
- FDA approval history
- Drug class: upper respiratory combinations
Related treatment guides
Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.