Guaifenesin and Hydrocodone (Oral)


Available orally in solution, in tablets, syrups, extended release tablets, capsules and liquid dosage forms, Guaifenesin and Hydrocodone are two medicines commonly used in combination to treat the most common symptoms associated with a cold. Together, they tackle persistent coughs and nasal congestion, which have usually developed as part of a cold.

Guaifenesin belongs to a group of medicines known as expectorants, which aim to reduce congestion in a patient's airways. It works to clear the phlegm or excess mucus from the throat and chest that typically arrives with congestion by thinning the texture of the mucus produced in the patient's lungs. Hydrocodone belongs to a family of medicines known as narcotic antitussives (or, more commonly, cough suppressants). It works by altering the response of the brain's cough center to reduce the urge to cough in the patient.

Guaifenesin and Hydrocodone are usually only available on prescription from a qualified, licensed physician.

In combination, Guaifenesin and Hydrocodone have also been used in the treatment of congestion caused by allergies or other viruses, including influenza (flu). A physician may also prescribe Guaifenesin and Hydrocodone for other, less common reasons not listed here.

Conditions Treated

  • Coughs and colds

Type Of Medicine

  • Expectorant

Side Effects

All medicines come with the risk of causing unwanted side effects alongside their desired effects. Not all of the following side effects may occur, but if they do, they may require medical assistance.

The following side effects are serious and patients should contact their physician immediately if they experience them.

  • Shallow, fast, slow or irregular breathing

Other, less medically serious side effects may occur in some patients. They do not normally require immediate medical attention, but patients who are concerned about their persistence should contact their physician or pharmacist. They may be able to recommend strategies for reducing or preventing certain side effects from appearing. The following side effects may disappear as the patient's body adapts to the medicine over the course of treatment.

  • Warming sensations

Some patients may also experience side effects not listed here. Patients who cannot find their side effects detailed above should check with their physician or healthcare professional to find out more. New side effects can also be reported to the FDA by calling 1-800-FDA-1088.


Patients should only take Guaifenesin and Hydrocodone according to their physician's original instructions and the instructions given on the label. Patients should never take more of it, less of it, take it more often or for longer than their physician has directed. Guaifenesin and Hydrocodone can become addictive if taken over a prolonged period of time, causing a physical or mental dependence. It also carries the risk of overdose, which can prove fatal.

If prescribed as a liquid, patients should carefully measure their doses using medical measuring spoons, cups or oral syringes for accuracy. A typical teaspoon a patient may have at home can vary in size, so it is important that patients use approved measuring equipment to ensure they get the correct dose. Patients who have questions about this should ask their pharmacist or physician.

Doses of Guaifenesin and Hydrocodone will vary from patient to patient, in line with their age, symptoms and a physician's assessment of a suitable treatment plan. Patients should always follow their physician's instructions or the instructions given on the label. The following information contains the average doses for Guaifenesin and Hydrocodone: some patients may be prescribed more or less than this. Patients should not alter their dose until their physician has agreed to the change.

Dosage instructions will depend on the strength of the formulation used. Physicians will also make decisions about the number of doses a day, the time between doses and the total length of treatment based on the severity and type of medical problem presenting in the patient.

In solution, Guaifenesin and Hydrocodone is typically given in 10 ml doses every four to six hours (as required) for the treatment of sneezing, nasal congestion or cough. Patients should never take more than six doses (a total of 60ml) in any 24 hour period. Guaifenesin and Hydrocodone is not recommended for use in children. Any dosing for children and infants should be decided by a qualified physician.

If a patient misses a dose of Guaifenesin and Hydrocodone, they should take it as soon as they remember, unless it is almost time for their next regular dose. If their next dose is almost due, they should skip the missed dose and carry on as normal on their dosing schedule. Patients should never double dose.

Major drug interactions:

Some medicines should never be used together. Other medicines can be used in combination, even though there may be a risk of interactions and additional side effects. A physician may take the decision to reduce or manage the risk of interactions, including reducing the dose of one or more medicines, or alter when and how the medications are taken by the patient. Patients should ensure that their physician has a full and accurate picture of all the substances they are taking, including prescription-only, over the counter, herbal remedies, vitamins, supplements and narcotics. The following medicines are known to have significant interactions with Guaifenesin and Hydrocodone. Other medicines not listed here may also interact with Guaifenesin and Hydrocodone.

Physicians do not advise taking Guaifenesin and Hydrocodone with the following medicines:

  • Naltrexone

The following list of medicines are not recommended for use in combination with Guaifenesin and Hydrocodone, as they are known to interact with each other to produce unwanted side effects or alter the effects of one or more medicines. A physician may choose to prescribe the following with Guaifenesin and Hydrocodone, but they will also usually recommend dosage changes or alter the frequency or timing of doses to reduce the risks.

  • Flunitrazepam

Taking Guaifenesin and Hydrocodone alongside the following medicines can lead to an increased risk of specific side effects, but a physician may decide that prescribing them in combination is the best course of treatment for certain patients. When prescribed together, a physician may adjust the doses, the frequency or the timing of use of one or more of the medicines to reduce the risk of interactions.

  • Escitalopram

Some medicines should also not be taken around the time of eating or eating specific kinds of foods to avoid the risk of interactions. Smoking or drinking alcohol may also raise a patient's risk of developing side effects from interactions with their medicines. The following non-medicinal interactions represent those most significant, but it is by no means a comprehensive list of all substances that may cause interactions.

Physicians typically do not recommend taking Guaifenesin and Hydrocodone with any of the following substances, but it can be unavoidable in certain circumstances. Again, a patient's physician may choose to alter the dose of medicines, their frequency or timing to reduce the risk of these types of interaction, or advise the patient to change their diet or lifestyle during the course of treatment.

  • Grapefruit juice

Patients who have additional medical issues may also experience problems associated with taking Guaifenesin and Hydrocodone. Patients who have the following conditions should fully inform their physician before accepting any prescription:

  • A history of narcotics use or drug dependency


A patient's physician should regularly review the patient's condition via scheduled appointments to check the progress of Guaifenesin and Hydrocodone. They should review whether the medicine is working and decide whether the patient should continue to take it. Patients who have concerns about their symptoms persisting or becoming worse should contact their physician.

Patients who have used an MAO inhibitor (known as an MAOI), including Marplan®, Eldepryl®, Parnate® or Nardil®, within the last two weeks should not take Guaifenesin and Hydrocodone.

Guaifenesin and Hydrocodone can become addictive and habit-forming among patients over time. Patients who start to notice no effect from their medicine should contact their physician and never take more than they have been prescribed.

If someone is believed to have taken an overdose of Guaifenesin and Hydrocodone, medical help should be sought immediately. Patients who have overdosed will have one or more of the following symptoms: difficulty or labored breathing, dark urine, slow, fast or irregular breathing, vomiting and nausea, blue or pale lips, pain above the stomach, pale skin or fingernails, constricted pupils or yellowed skin or eyes.

Guaifenesin and Hydrocodone has also been known to make patients feel drowsy or dizzy. Patients who believe they may be susceptible to this should not use machinery, drive or do anything else that may pose a risk should they start to feel not alert.

Guaifenesin and Hydrocodone also contribute to the effects of CNS depressants (medications that can make patients feel less alert or sleepy) and alcohol. Some CNS depressants are medicines used to treat colds, allergies, tranquillisers, sleeping medicines, narcotics, pain medications, sedatives, medications to treat seizures and barbiturates, anesthetics, dental anesthetics and muscle relaxants. Patients who take any of the above substances should check with their physician before taking Guaifenesin and Hydrocodone.

Guaifenesin and Hydrocodone can also cause severe constipation amongst some patients. Physicians may recommend certain laxatives or advise on drinking plenty of fluids or increasing the amount of fibre in a patient's diet to counteract this. Patients should monitor their condition closely and always follow their physician's advice, as long-term constipation can lead to more severe issues.

Patients should not start or stop taking any medicines or substances without consulting their physician, including prescription medications, over the counter medicines, herbal remedies, vitamins, supplements and narcotics.

Guaifenesin and Hydrocodone is not recommended for use in pediatric care. Hydrocodone has been known to cause breathing difficulties in children under the age of six and can lead to death. Studies have not been carried out into the relationship between age and the use of Guaifenesin and Hydrocodone in combination.

Studies have not demonstrated a link between problems experienced by elderly patients (in geriatric care) and the usefulness of Guaifenesin and Hydrocodone. Elderly patients are, however, more likely to have age-related liver, kidney or heart issues. Physicians who wish to prescribe Guaifenesin and Hydrocodone for an elderly patient should review the dose and exercise caution.

Guaifenesin and Hydrocodone is not recommended for use during pregnancy or for breastfeeding women. Animal studies have shown potential adverse effects on fetuses, but no human studies have been conducted. Similarly, there are no appropriate studies showing a link between problems and use while breastfeeding. Physicians should carefully weigh the benefits against the potential risks before prescribing Guaifenesin and Hydrocodone for patients who are pregnant or breastfeeding.


As with most oral medicines, Guaifenesin and Hydrocodone should be stored at room temperature, away from direct sunlight, moisture and heat. Always store medicines in their original packaging, complete with the original instruction label, firmly closely and kept out of the reach of children or vulnerable adults. Always keep Guaifenesin and Hydrocodone from freezing.

Patients should not stockpile or keep medicines that are out of date or no longer required. Patients with unwanted medicines should consult their physician or pharmacist for local take-back programs or other ways to safely dispose of medicines. Never flush medicines down the toilet or rinse them down the sink.


Guaifenesin and Hydrocodone is a combined medicine which, when taken orally, is used to treat coughs and congestion in adults, caused by the common cold. Guaifenesin works by thinning the consistency of mucus that lines the airways and lungs, loosening it where it becomes congested. Guifenesin belongs to a group of medicines known as expectorants. Hydrocodone belongs to a family of medicines known as antitussives, otherwise known as narcotic cough suppressants. It works to reduce the urge to cough in patients by changing the brain's response in a certain area.

Guaifenesin and Hydrocodone should not be prescribed to treat long-term problems with breathing or lingering coughs caused by smoking. It should not be used to treat emphysema, chronic bronchitis or asthma, unless advised by a qualified physician.