Mar-Cof Cg (guaifenesin W/cod) Liq
WARNING: For all patients taking this drug:This drug has an opioid drug in it. Opioid drugs can put you at risk for drug use disorder. Misuse or abuse of this drug can lead to overdose and death. If you have questions, talk with your doctor.You will be watched closely to make sure you do not misuse this drug or develop drug use disorder.This drug has an opioid drug in it. Severe side effects have happened when opioid drugs were used with benzodiazepines, alcohol, marijuana or other forms of cannabis, or prescription or OTC drugs that may cause drowsiness or slowed actions. This includes slow or troubled breathing and death. Benzodiazepines include drugs like alprazolam, diazepam, and lorazepam. Benzodiazepines may be used to treat many health problems like anxiety, trouble sleeping, or seizures. If you have questions, talk with the doctor.Many drugs interact with this drug and can raise the chance of side effects like deadly breathing problems. Talk with your doctor and pharmacist to make sure it is safe to use this drug with all of your drugs.Do not take with alcohol or products that have alcohol. Unsafe and sometimes deadly effects may happen.Get medical help right away if you feel very sleepy, very dizzy, or if you pass out. Caregivers or others need to get medical help right away if the patient does not respond, does not answer or react like normal, or will not wake up.This drug may cause very bad and sometimes deadly breathing problems. Call your doctor right away if you have slow, shallow, or trouble breathing.Children:This drug is not for use in children younger than 18 years of age. The benefits of taking this drug for a cough due to allergies, a cold, or other infection do not outweigh the risks in children. If your child has been given this drug or if you have any questions, talk with your child's doctor. @ COMMON USES: It is used to thin mucus so it can be taken from the body by coughing.It is used to relieve coughing.
Drug Class
Antitussive, Expectorant
Pharmacologic Class
Opioid Analgesic (Codeine), Expectorant (Guaifenesin)
Pregnancy Category
Category C
FDA Approved
Jan 1970
DEA Schedule
Schedule V
Overview
What is this medicine?
This medicine contains two active ingredients: guaifenesin and codeine. Guaifenesin helps to thin and loosen mucus in your lungs, making it easier to cough up. Codeine helps to calm your cough by acting on the cough center in your brain. It is used to relieve cough and chest congestion caused by the common cold, bronchitis, or other breathing illnesses.
How to Use This Medicine
Taking Your Medication Correctly
To ensure you get the most out of your medication, follow these steps:
Take your medication exactly as directed by your doctor.
Read all the information provided with your medication and follow the instructions carefully.
You can take this medication with or without food. If it causes stomach upset, take it with food to help minimize this side effect.
Drink plenty of non-caffeinated liquids, unless your doctor advises you to limit your fluid intake.
When taking the liquid form of this medication, measure your dose carefully using the measuring device provided. If one is not included, ask your pharmacist for a suitable device to measure your medication accurately.
Storing and Disposing of Your Medication
To keep your medication safe and effective:
Store it at room temperature in a dry place, avoiding the bathroom.
Keep your medication out of sight and reach of children and pets, and store it in a secure location where others cannot access it. Consider using a locked box or area to store your medication.
Dispose of unused or expired medication properly. Do not flush it down the toilet or pour it down the drain unless instructed to do so by your doctor or pharmacist. If you have questions about disposing of your medication, consult with your pharmacist, who may be aware of drug take-back programs in your area.
What to Do If You Miss a Dose
If you take this medication on a regular schedule:
Take the missed dose as soon as you remember.
If it is close to the time for your next dose, skip the missed dose and resume your regular dosing schedule.
Do not take two doses at the same time or take extra doses.
If you take this medication as needed:
Do not take it more frequently than directed by your doctor.
To ensure you get the most out of your medication, follow these steps:
Take your medication exactly as directed by your doctor.
Read all the information provided with your medication and follow the instructions carefully.
You can take this medication with or without food. If it causes stomach upset, take it with food to help minimize this side effect.
Drink plenty of non-caffeinated liquids, unless your doctor advises you to limit your fluid intake.
When taking the liquid form of this medication, measure your dose carefully using the measuring device provided. If one is not included, ask your pharmacist for a suitable device to measure your medication accurately.
Storing and Disposing of Your Medication
To keep your medication safe and effective:
Store it at room temperature in a dry place, avoiding the bathroom.
Keep your medication out of sight and reach of children and pets, and store it in a secure location where others cannot access it. Consider using a locked box or area to store your medication.
Dispose of unused or expired medication properly. Do not flush it down the toilet or pour it down the drain unless instructed to do so by your doctor or pharmacist. If you have questions about disposing of your medication, consult with your pharmacist, who may be aware of drug take-back programs in your area.
What to Do If You Miss a Dose
If you take this medication on a regular schedule:
Take the missed dose as soon as you remember.
If it is close to the time for your next dose, skip the missed dose and resume your regular dosing schedule.
Do not take two doses at the same time or take extra doses.
If you take this medication as needed:
Do not take it more frequently than directed by your doctor.
Lifestyle & Tips
- Avoid alcohol while taking this medication, as it can increase drowsiness and dizziness.
- Do not drive or operate heavy machinery until you know how this medication affects you, as it can cause drowsiness.
- Drink plenty of fluids (water, juice) to help loosen mucus and make it easier to cough up.
- Avoid smoking, as it can worsen cough and lung irritation.
- Do not take more than the prescribed dose or more often than directed, as this can lead to serious side effects, including overdose.
Available Forms & Alternatives
Available Strengths:
Dosing & Administration
Adult Dosing
Standard Dose:
10 mL (100 mg guaifenesin/10 mg codeine) orally every 4 to 6 hours as needed
Dose Range:
10 - 20 mg
Condition-Specific Dosing:
maxDailyDose:
60 mL (600 mg guaifenesin/60 mg codeine) in 24 hours
Pediatric Dosing
Neonatal:
Not established (Contraindicated)
Infant:
Not established (Contraindicated)
Child:
Contraindicated in children younger than 12 years of age
Adolescent:
Not recommended for adolescents 12 to 18 years of age who have other risk factors that may increase their sensitivity to the respiratory depressant effects of codeine
Dose Adjustments
Renal Impairment:
Mild:
No specific adjustment recommended, monitor for increased adverse effects
Moderate:
Use with caution, consider dose reduction and extended dosing interval
Severe:
Use with caution, significant dose reduction and extended dosing interval may be necessary. Codeine and its metabolites accumulate.
Dialysis:
Codeine and its metabolites are dialyzable to some extent, but caution is advised. Avoid use if possible.
Hepatic Impairment:
Mild:
Use with caution, monitor for increased adverse effects
Moderate:
Use with caution, consider dose reduction and extended dosing interval. Codeine metabolism may be impaired.
Severe:
Contraindicated or use with extreme caution and significant dose reduction. Codeine metabolism is significantly impaired.
Confidence:
Medium
Pharmacology
Mechanism of Action
Guaifenesin is an expectorant that works by thinning and loosening mucus in the airways, making it easier to cough up. Codeine is an opioid antitussive that acts centrally on the cough center in the medulla to suppress cough.
Pharmacokinetics
Absorption:
Bioavailability:
Codeine: ~50-70%; Guaifenesin: Not well quantified, but rapidly absorbed
Tmax:
Codeine: 0.5-1 hour; Guaifenesin: ~1 hour
FoodEffect:
Food may slightly delay absorption but does not significantly affect extent of absorption.
Distribution:
Vd:
Codeine: ~2.6 L/kg; Guaifenesin: Not well quantified
ProteinBinding:
Codeine: ~7-25%; Guaifenesin: Not well quantified
CnssPenetration:
Codeine: Yes (crosses blood-brain barrier); Guaifenesin: Limited
Elimination:
HalfLife:
Codeine: ~2-4 hours; Guaifenesin: ~1 hour
Clearance:
Codeine: ~800 mL/min; Guaifenesin: Not well quantified
ExcretionRoute:
Renal (primarily as metabolites)
Unchanged:
Codeine: ~5-10%; Guaifenesin: Negligible
Pharmacodynamics
OnsetOfAction:
15-30 minutes
PeakEffect:
1-2 hours
DurationOfAction:
4-6 hours
Safety & Warnings
BLACK BOX WARNING
WARNING: RISKS FROM CONCOMITANT USE WITH BENZODIAZEPINES OR OTHER CNS DEPRESSANTS; ADDICTION, ABUSE, AND MISUSE; RESPIRATORY DEPRESSION; ACCIDENTAL INGESTION; ULTRA-RAPID METABOLISM OF CODEINE AND OTHER RISK FACTORS FOR OPIOID-RELATED ADVERSE REACTIONS IN CHILDREN; NEONATAL OPIOID WITHDRAWAL SYNDROME. Concomitant use of opioids with benzodiazepines or other CNS depressants, including alcohol, may result in profound sedation, respiratory depression, coma, and death. Reserve concomitant prescribing for use in patients for whom alternative treatment options are inadequate. Limit dosages and durations to the minimum required. Follow patients for signs and symptoms of respiratory depression and sedation. Codeine-containing products expose patients and other users to the risks of opioid addiction, abuse, and misuse, which can lead to overdose and death. Assess each patient’s risk prior to prescribing, and monitor all patients regularly for the development of these behaviors and conditions. Serious, life-threatening, or fatal respiratory depression may occur. Monitor for respiratory depression, especially during initiation of codeine-containing products or following a dose increase. Accidental ingestion of even one dose of codeine-containing products, especially by children, can result in a fatal overdose of codeine. Life-threatening respiratory depression and death have occurred in children who received codeine. Most of the reported cases occurred following tonsillectomy and/or adenoidectomy and were associated with evidence of ultra-rapid metabolism of codeine to morphine. Codeine-containing products are contraindicated in children younger than 12 years of age and in adolescents 12 to 18 years of age following tonsillectomy and/or adenoidectomy. Breastfeeding is not recommended. Prolonged use of opioid analgesics during pregnancy can result in neonatal opioid withdrawal syndrome, which may be life-threatening if not recognized and treated, and requires management according to protocols developed by neonatology experts.
Side Effects
Urgent Side Effects: Seek Medical Help Right Away
Although rare, some people may experience severe and potentially life-threatening side effects while taking this medication. If you notice any of the following symptoms, contact your doctor immediately or seek emergency medical attention:
Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin with or without fever
+ Wheezing
+ Tightness in the chest or throat
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Severe dizziness or fainting
Chest pain or pressure, rapid heartbeat, or irregular heartbeat
Breathing difficulties, slow breathing, or shallow breathing
Noisy breathing
Sleep apnea (breathing problems during sleep)
Confusion
Hallucinations (seeing or hearing things that are not there)
Mood changes
Seizures
Severe headache
Difficulty urinating
Shakiness
Changes in vision
Severe constipation or stomach pain, which may indicate a serious bowel problem
Other Possible Side Effects
Like all medications, this drug can cause side effects. While many people may not experience any side effects or only mild ones, it's essential to discuss any concerns with your doctor. If you experience any of the following side effects or any other unusual symptoms that bother you or persist, contact your doctor for advice:
Constipation
Upset stomach or vomiting
Dizziness, drowsiness, fatigue, or weakness
* Excessive sweating
This list is not exhaustive, and you may experience other side effects not mentioned here. If you have questions or concerns about side effects, consult your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
Although rare, some people may experience severe and potentially life-threatening side effects while taking this medication. If you notice any of the following symptoms, contact your doctor immediately or seek emergency medical attention:
Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin with or without fever
+ Wheezing
+ Tightness in the chest or throat
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Severe dizziness or fainting
Chest pain or pressure, rapid heartbeat, or irregular heartbeat
Breathing difficulties, slow breathing, or shallow breathing
Noisy breathing
Sleep apnea (breathing problems during sleep)
Confusion
Hallucinations (seeing or hearing things that are not there)
Mood changes
Seizures
Severe headache
Difficulty urinating
Shakiness
Changes in vision
Severe constipation or stomach pain, which may indicate a serious bowel problem
Other Possible Side Effects
Like all medications, this drug can cause side effects. While many people may not experience any side effects or only mild ones, it's essential to discuss any concerns with your doctor. If you experience any of the following side effects or any other unusual symptoms that bother you or persist, contact your doctor for advice:
Constipation
Upset stomach or vomiting
Dizziness, drowsiness, fatigue, or weakness
* Excessive sweating
This list is not exhaustive, and you may experience other side effects not mentioned here. If you have questions or concerns about side effects, consult your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
Seek Immediate Medical Attention If You Experience:
- Slow, shallow, or difficult breathing
- Extreme drowsiness or difficulty waking up
- Bluish lips or skin
- Severe dizziness or lightheadedness
- Confusion
- Severe constipation
- Signs of an allergic reaction (rash, itching, swelling, severe dizziness, trouble breathing)
Before Using This Medicine
Before Taking This Medication: Important Information to Share with Your Doctor
It is essential to inform your doctor about the following:
Any allergies you have to this medication, its components, or other substances, including foods and drugs. Describe the allergic reaction and its symptoms.
Existing health conditions, such as:
+ Respiratory issues like asthma, breathing difficulties, or sleep apnea
+ Elevated carbon dioxide levels in the blood
+ Stomach or bowel obstruction or narrowing
Respiratory symptoms, including:
+ A cough producing excessive mucus
+ A chronic cough caused by smoking or exposure to smoke
+ Lung conditions like asthma or emphysema
Recent use (within the last 14 days) of certain medications for depression or Parkinson's disease, including isocarboxazid, phenelzine, tranylcypromine, selegiline, or rasagiline, as this may lead to severely high blood pressure
Current use of specific drugs, such as buprenorphine, butorphanol, linezolid, methylene blue, nalbuphine, or pentazocine
If your doctor has informed you that you are a rapid metabolizer of certain medications
* If you are breastfeeding, as you should not breastfeed while taking this medication
This list is not exhaustive. It is crucial to discuss all your medications (prescription, over-the-counter, natural products, and vitamins) and health conditions with your doctor and pharmacist to ensure safe use. Never start, stop, or adjust the dosage of any medication without consulting your doctor.
It is essential to inform your doctor about the following:
Any allergies you have to this medication, its components, or other substances, including foods and drugs. Describe the allergic reaction and its symptoms.
Existing health conditions, such as:
+ Respiratory issues like asthma, breathing difficulties, or sleep apnea
+ Elevated carbon dioxide levels in the blood
+ Stomach or bowel obstruction or narrowing
Respiratory symptoms, including:
+ A cough producing excessive mucus
+ A chronic cough caused by smoking or exposure to smoke
+ Lung conditions like asthma or emphysema
Recent use (within the last 14 days) of certain medications for depression or Parkinson's disease, including isocarboxazid, phenelzine, tranylcypromine, selegiline, or rasagiline, as this may lead to severely high blood pressure
Current use of specific drugs, such as buprenorphine, butorphanol, linezolid, methylene blue, nalbuphine, or pentazocine
If your doctor has informed you that you are a rapid metabolizer of certain medications
* If you are breastfeeding, as you should not breastfeed while taking this medication
This list is not exhaustive. It is crucial to discuss all your medications (prescription, over-the-counter, natural products, and vitamins) and health conditions with your doctor and pharmacist to ensure safe use. Never start, stop, or adjust the dosage of any medication without consulting your doctor.
Precautions & Cautions
It is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication. Adhere strictly to the dosage instructions provided by your doctor, as taking more than prescribed may increase the risk of severe side effects. Do not exceed the recommended duration of use, and only take this medication for the length of time specified by your doctor.
To minimize the risk of dizziness or fainting, rise slowly from a seated or lying position, and exercise caution when navigating stairs. Additionally, be aware that this medication may impair your ability to drive or perform tasks that require alertness, so it is crucial to assess how it affects you before engaging in such activities.
Long-term use of this medication can lead to dependence. If you have been taking it regularly and stop abruptly, you may experience withdrawal symptoms. Do not discontinue use without consulting your doctor first, and report any adverse effects to your doctor promptly.
Avoid concomitant use of this medication with other strong pain medications or pain patches without prior consultation with your doctor. Furthermore, be aware that this medication may interfere with certain laboratory tests, so inform all your healthcare providers and laboratory personnel that you are taking this medication.
Keep this medication out of reach of children, as accidental ingestion can be fatal. If a child accidentally ingests this medication, seek immediate medical attention. Elderly patients (65 years and older) should exercise caution when using this medication, as they may be more susceptible to side effects.
Children, particularly those with pre-existing breathing problems, are at a higher risk of experiencing severe side effects, including life-threatening respiratory problems. It is crucial to discuss this risk with your doctor. If you are pregnant or become pregnant while taking this medication, inform your doctor immediately, as it may harm the unborn baby. Prolonged use during pregnancy can lead to withdrawal symptoms in the newborn, which can be life-threatening if left untreated.
To minimize the risk of dizziness or fainting, rise slowly from a seated or lying position, and exercise caution when navigating stairs. Additionally, be aware that this medication may impair your ability to drive or perform tasks that require alertness, so it is crucial to assess how it affects you before engaging in such activities.
Long-term use of this medication can lead to dependence. If you have been taking it regularly and stop abruptly, you may experience withdrawal symptoms. Do not discontinue use without consulting your doctor first, and report any adverse effects to your doctor promptly.
Avoid concomitant use of this medication with other strong pain medications or pain patches without prior consultation with your doctor. Furthermore, be aware that this medication may interfere with certain laboratory tests, so inform all your healthcare providers and laboratory personnel that you are taking this medication.
Keep this medication out of reach of children, as accidental ingestion can be fatal. If a child accidentally ingests this medication, seek immediate medical attention. Elderly patients (65 years and older) should exercise caution when using this medication, as they may be more susceptible to side effects.
Children, particularly those with pre-existing breathing problems, are at a higher risk of experiencing severe side effects, including life-threatening respiratory problems. It is crucial to discuss this risk with your doctor. If you are pregnant or become pregnant while taking this medication, inform your doctor immediately, as it may harm the unborn baby. Prolonged use during pregnancy can lead to withdrawal symptoms in the newborn, which can be life-threatening if left untreated.
Overdose Information
Overdose Symptoms:
- Slowed or stopped breathing
- Extreme drowsiness or unresponsiveness
- Pinpoint pupils
- Cold, clammy skin
- Limp muscles
- Bluish discoloration of lips or fingernails
- Loss of consciousness
What to Do:
Seek immediate emergency medical attention. Call 911 or your local emergency number. In the U.S., you can also contact a poison control center at 1-800-222-1222. Have naloxone available if prescribed and trained on its use.
Drug Interactions
Contraindicated Interactions
Major Interactions
- Other opioid analgesics (increased risk of respiratory depression, sedation, hypotension)
- Benzodiazepines and other CNS depressants (increased risk of profound sedation, respiratory depression, coma, and death)
- CYP2D6 inhibitors (e.g., bupropion, duloxetine, amiodarone, ritonavir) - may decrease conversion of codeine to morphine, reducing efficacy
- CYP2D6 inducers (e.g., rifampin, carbamazepine, phenytoin) - may increase conversion of codeine to morphine, increasing risk of adverse effects
- Anticholinergics (e.g., atropine, scopolamine) - increased risk of urinary retention and/or severe constipation
Moderate Interactions
- Monoamine Oxidase Inhibitors (MAOIs) - potential for serotonin syndrome or increased opioid effects (use with caution, allow 14 days washout)
- Muscle relaxants (e.g., cyclobenzaprine, baclofen) - additive CNS depression
- Antihistamines (sedating, e.g., diphenhydramine) - additive CNS depression
Minor Interactions
- Not specifically noted for guaifenesin/codeine combination beyond the above.
Monitoring
Baseline Monitoring
Respiratory rate and depth
Rationale: To assess baseline respiratory function before initiating opioid therapy.
Timing: Prior to first dose
Level of consciousness/sedation
Rationale: To establish baseline mental status and identify risk for excessive sedation.
Timing: Prior to first dose
Cough severity and characteristics
Rationale: To assess the need for antitussive therapy and establish a baseline for efficacy monitoring.
Timing: Prior to first dose
Routine Monitoring
Respiratory rate and depth
Frequency: Periodically during therapy, especially after dose adjustments or initiation of concomitant CNS depressants
Target: Normal for age, without signs of distress
Action Threshold: Respiratory rate <10 breaths/min in adults, or signs of shallow breathing, cyanosis; administer naloxone if severe.
Level of consciousness/sedation
Frequency: Periodically during therapy
Target: Alert and oriented, able to perform activities of daily living
Action Threshold: Excessive drowsiness, difficulty arousing, confusion; reduce dose or discontinue.
Bowel function (for constipation)
Frequency: Daily
Target: Regular bowel movements
Action Threshold: No bowel movement for >3 days; initiate laxative regimen.
Efficacy of cough suppression
Frequency: Daily or as needed
Target: Reduced frequency and severity of cough
Action Threshold: Persistent severe cough; re-evaluate therapy.
Symptom Monitoring
- Drowsiness
- Dizziness
- Nausea
- Vomiting
- Constipation
- Difficulty breathing or shallow breathing
- Confusion
- Lightheadedness
- Itching
Special Patient Groups
Pregnancy
Category C. Use only if the potential benefit justifies the potential risk to the fetus. Prolonged use during pregnancy can result in neonatal opioid withdrawal syndrome (NOWS), which may be life-threatening.
Trimester-Specific Risks:
First Trimester:
Potential for congenital malformations (e.g., neural tube defects, cardiac defects) with opioid exposure, though data for codeine specifically is mixed.
Second Trimester:
Risk of fetal growth restriction and premature delivery with prolonged opioid use.
Third Trimester:
High risk of neonatal opioid withdrawal syndrome (NOWS) if used chronically. Risk of respiratory depression in the neonate if used close to delivery.
Lactation
Contraindicated. Codeine is metabolized to morphine, and in mothers who are ultra-rapid metabolizers of codeine, potentially fatal levels of morphine can be passed to the breastfed infant, leading to serious adverse reactions including respiratory depression and death. Breastfeeding is not recommended.
Infant Risk:
High (risk of serious adverse reactions including respiratory depression, sedation, and death due to morphine exposure).
Pediatric Use
Contraindicated in children younger than 12 years of age. Not recommended for adolescents 12 to 18 years of age who have other risk factors that may increase their sensitivity to the respiratory depressant effects of codeine (e.g., obesity, sleep apnea, severe lung disease).
Geriatric Use
Use with caution. Elderly patients may be more sensitive to the respiratory depressant and CNS effects of codeine. Start with lower doses and titrate slowly. Increased risk of falls, constipation, and urinary retention.
Clinical Information
Clinical Pearls
- Due to the risks associated with codeine, especially in children and breastfeeding mothers, this combination product should be used only when non-opioid alternatives are inadequate.
- Educate patients on the signs of respiratory depression and the importance of not exceeding the recommended dose.
- Advise patients to avoid alcohol and other CNS depressants while taking this medication.
- Monitor for constipation, a common side effect of codeine, and recommend appropriate management (e.g., increased fluid intake, fiber, laxatives).
- The expectorant effect of guaifenesin requires adequate hydration; encourage fluid intake.
Alternative Therapies
- Dextromethorphan (non-opioid antitussive)
- Benzonatate (non-opioid antitussive)
- Guaifenesin monotherapy (expectorant)
- Humidifiers and saline nasal sprays for congestion and cough relief
- Honey for cough relief
Cost & Coverage
Average Cost:
Varies widely, typically $15-$50 per 120 mL bottle
Generic Available:
Yes
Insurance Coverage:
Tier 2 or 3 (often requires prior authorization due to codeine content and pediatric restrictions)
General Drug Facts
If your symptoms or health issues persist or worsen, it is essential to contact your doctor for further guidance. To ensure your safety, never share your medication with others or take someone else's medication. Some medications may come with an additional patient information leaflet, so it's a good idea to check with your pharmacist for more information. If you have any questions or concerns about this medication, don't hesitate to discuss them with your doctor, nurse, pharmacist, or other healthcare provider. In the event of a suspected overdose, immediately call your local poison control center or seek medical attention. When seeking help, be prepared to provide details about the medication taken, the amount, and the time it happened.