Codeine and Guaifenesin

  • Generic Name or Active Ingridient: Codeine
Drug Class: Codeine And Guaifenesin > Codeine > Opiate > Opioids > Opioid Agonist > Analgesic.


Physicians prescribe codeine and guaifenesin to treat symptoms associated with upper respiratory infections or the common cold. Codeine is a cough suppressant while guaifenesin is an expectorant - it loosens up mucus congestion in your throat and lungs, making it easier to cough out. Use codeine and guaifenesin to relieve symptoms so you can sleep through the night, go to work or attend class. This product is not intended to treat coughs caused by smoking, asthma or emphysema. Learn More About Codeine and Guaifenesin Uses


There are dozens of brand name preparations including codeine and guaifenesin; one of the most popular brands is Robitussin AC.

Codeine and guaifenesin preparations are available as a capsule, tablet or syrup. The oral capsule is available in strengths of 9 mg of codeine with 200 mg of guaifenesin with a suggested dose of two capsules every four hours, not to exceed 12 capsules in a 24-hour period. The typical dose for oral tablets is one tablet every four hours as needed, not to exceed six tablets in a day. Oral tablets come in varying strengths of codeine and guaifenesin, including 10 mg/300 mg, 10 mg /400 mg and 20 mg /400 mg. A 5 ml dose of the syrup form of this drug contains 6.3 mg to 10 mg of codeine and 100 mg to 300 mg of guaifenesin.

Children's doses vary widely; discuss your child's dosage of codeine and guaifenesin with her pediatrician. Do not give codeine and guaifenesin to a child younger than four years old. Talk with your pediatrician before giving cough and cold preparations to a child; death can occur from misuse of these products in very young children.

Take this preparation with food if codeine and guaifenesin upset your stomach. Increase your intake of water to thin mucus congestion to make it easier to cough up.

Doctors typically prescribe codeine and guaifenesin to be taken only when you need relief from your symptoms, so you don't normally have to worry about missed doses. If your physician has recommended that you take codeine and guaifenesin on a schedule and you miss a dose, take the missing dose as soon as you remember. If it is nearly time to take another dose and you can tolerate the symptoms, skip the missed dose and resume your regular schedule.

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Codeine and guaifenesin work together to reduce cough and congestion. Codeine works by acting directly on the part of your brain responsible for the cough reflex. Your brain is simply unaware of the need to cough. Guaifenesin thins mucus to make it easier to cough it out of your lungs and throat.

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Anyone can suffer an allergic reaction to any medication. Allergic reaction is a serious medical condition that can deteriorate rapidly into a life-threatening emergency. Seek medical help immediately if you think you are suffering a reaction to codeine and guaifenesin.

Symptoms of an allergic reaction include:

  • Hives.
  • Difficulty Breathing.
  • Swelling of your Face, Lips, Tongue or Throat.

Guaifenesin is a common ingredient in many combination medications. Check the labels of all medications to see if they contain guaifenesin or another expectorant. Using several products at once may cause you to get too much guaifenesin. Talk with your pharmacist if you are unsure if a product contains an expectorant like guaifenesin.

Tell your doctor about your medical history. She may change your dosage of codeine and guaifenesin or switch you to a different medication if you have had a history of certain medical conditions. This medication may worsen your disease, or your medical condition may interfere with the way codeine and guaifenesin works. Notify your physician if your existing medical conditions worsen while you are taking codeine and guaifenesin.

Tell your physician about any significant illnesses or conditions, including:

  • Heart Disease, Heart Rhythm Disorder.
  • Asthma, COPD, Emphysema or Other Breathing Disorders.
  • History of Head Injury or Brain Tumor.
  • Epilepsy or Other Seizure Disorder.
  • Stomach or Intestinal Disorder.
  • Adrenal Gland Disorders.
  • Curvature of the Spine.
  • Thyroid Disorder.
  • Liver or Kidney Disease.
  • Enlarged Prostate.
  • History of Depression, Mental Illness or Drug Addiction.

This medication may make you dizzy or drowsy; furthermore, codeine and guaifenesin may impair your decision-making. Do not operate heavy machinery, drive a vehicle or engage in behavior that requires you make quick decisions.

Do not drink alcohol while taking codeine and guaifenesin. Alcohol increases your risk for side effects associated with codeine and guaifenesin.

This opioid can be habit-forming, especially if you have been taking high doses or using codeine and guaifenesin for a long time. Tell your doctor if your prescription stops working to relieve your symptoms; this may be a sign you are developing a tolerance to codeine. Your physician may adjust your dosage or switch you to a different pain medication. Do not take higher doses or use codeine and guaifenesin more frequently in an effort to relieve your symptoms. Stop using codeine and guaifenesin when recommended. Tell your physician if you have trouble quitting this medication.

Some codeine and guaifenesin preparations contain sugar or an artificial sweetener. Before using codeine and guaifenesin, tell your doctor if you have diabetes or phenylketonuria, or PKU.

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The FDA classifies codeine and guaifenesin as pregnancy category C, which means scientists do not yet know if taking this drug will harm your unborn child. Tell your physician if you are pregnant or plan to become pregnant while taking this preparation. Codeine does pass into breast milk; do not use this medication while breastfeeding your baby. Some babies experience life-threatening side effects when breastfed by mothers who have used codeine.

Do not quit taking codeine and guaifenesin suddenly unless directed to do so by your physician. Stopping the use of codeine and guaifenesin abruptly may cause unpleasant withdrawal symptoms. Wean yourself from this medication by taking smaller doses less frequently.

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Drug Interactions

This medication may interact with other drugs in unsafe or unfavorable ways. Give your doctor and pharmacist a complete and updated list of all your prescriptions, over-the-counter drugs and herbal remedies. Do not start or stop any medication without telling your physician.

Do not take other medications that make you drowsy or sleepy. Muscle relaxers, tranquilizers, sedatives and cough and cold medicines may enhance drowsiness caused by codeine and guaifenesin. Medicines for seizures or depression may also have this effect.

Your doctor may alter the dosage of codeine and guaifenesin or switch you to a different prescription if you already take certain medications to treat other illnesses. Tell your doctor if you are taking Tagamet, quinidine, Narcan or Vivitrol.

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Side effects

Patients report some common side effects after taking codeine and guaifenesin. Older individuals are more likely to experience side effects. Tell your doctor if these side effects become unbearable or if they don't go away on their own. Common side effects include:

  • Dizziness, Drowsiness, Headache.
  • Warmth, Redness or Tingling Under Your Skin.
  • Nausea, Vomiting, Upset Stomach.
  • Constipation.
  • Skin Rash or Itching.

Some side effects can be serious, even life-threatening. Contact your doctor or local emergency room right away if you experience serious side effects such as:

  • Severe Dizziness or Drowsiness.
  • Confusion, Hallucinations, Unusual Thoughts or Behavior.
  • Urinating Less Than Usual or Not at All.
  • Slow Heart Rate.
  • Weak Pulse.
  • Fainting.
  • Weakness.
  • Shallow Breathing.

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Do not take more codeine and guaifenesin than prescribed or take it more often than recommended, as this may result in overdose. Overdose of codeine and guaifenesin is a serious, life-threatening condition. If you think you or someone you know has taken an overdose, contact poison control center at 1-800-222-1222 or go to the emergency room. Overdose symptoms include:

  • Extreme Dizziness or Drowsiness.
  • Nausea or Vomiting.
  • Sweating.
  • Confusion or Hallucinations.
  • Cold and Clammy Skin.
  • Blue-Colored Lips or Fingernails.
  • Weak or Limp Muscles.
  • Pinpoint Pupils.
  • Weak Pulse.
  • Slow Breathing.
  • Fainting.
  • Seizures

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Experts believe about 9 percent of the population have misused opioids over the course of their lifetimes, including illegal and prescription drugs. This medication, like other opioids, is a favorite among recreational users because it gets them high. Abusers can buy codeine on the street, present phony prescriptions to pharmacies, go to multiple doctors or steal it from pharmacies, friends or family.

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If you take high doses of codeine, or you use this drug for a long time, your body may grow physically dependent on this opioid. Dependence means your body relies on codeine to prevent symptoms of withdrawal. You may experience unpleasant, flu-like symptoms when you stop taking codeine. It takes some time for your body chemistry to return to normal. Withdrawal symptoms are a predictable, normal physiological reaction to your body's dependence on a chemical and not necessarily an indication of illicit or recreational drug abuse. Not everyone experiences withdrawal in exactly the same way. Sometimes people who had been given opioids in the hospital don't realize they are suffering from withdrawal and attribute the unpleasant physical symptoms to the flu. A person who has associated his symptoms with withdrawal might start craving codeine because he knows using the drug will ease his discomfort. Withdrawal symptoms may be so strong in some individuals that the physical discomfort prevents them from quitting codeine. More Information about Withdrawal from Codeine and Guaifenesin


Rehabilitation specialists combine supportive care and medications to detoxify your body from codeine use. Medications ease withdrawal symptoms and cleanse the opioid from your body to speed restoration of your chemical balance. Supportive care typically involves counseling and other social services to increase your chances for success. Rapid detox is a new, humane way method of detoxifying your system. Physicians administer sedatives and anesthesia along with the regular detoxification medications so that you are sedated during withdrawal, unaware of the pleasant flu-like symptoms that prevented you from quitting on your own. You awaken refreshed and stabilized, already finished with the physically demanding part of rehabilitation. Learn More About Codeine and Guaifenesin Detoxification Programs


This drug should be stored at room temperature. Keep codeine and guaifenesin away from excessive heat, light and moisture. Put this and all medications out of the reach of children and pets. Do not share codeine and guaifenesin with others. Keep this opioid away from adults who might mistakenly or purposefully take this drug. Monitor your medications and account for all doses.

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