Usage
- This combination medication is prescribed for the temporary relief of cough and upper respiratory symptoms, including nasal congestion, associated with the common cold or allergies. It is also used as an expectorant to treat coughs by thinning and loosening mucus in the airways.
- Pharmacological Classification: This is a combination product containing a first-generation antihistamine (chlorpheniramine), a cough suppressant (dextromethorphan), an expectorant (guaifenesin), and a topical anesthetic/cooling agent (menthol).
- Mechanism of Action: Chlorpheniramine blocks histamine H1 receptors, reducing allergic symptoms. Dextromethorphan suppresses the cough reflex in the brain. Guaifenesin thins and loosens mucus in the airways, making it easier to cough up. Menthol provides a cooling sensation and soothes irritated airways.
Alternate Names
- This combination, as it contains menthol and lacks phenylephrine, does not have a universally recognized International Nonproprietary Name (INN). The individual components have the following INNs: chlorpheniramine maleate, dextromethorphan hydrobromide, guaifenesin, and menthol.
- Brand Names: Numerous brand names exist for similar combinations (often including phenylephrine), but one specific brand matching this exact combination with menthol and without phenylephrine is harder to pinpoint and may vary regionally. Always verify the exact composition of any specific brand-name product. A combination syrup named Cofgel was mentioned in the sources.
How It Works
- Pharmacodynamics: Chlorpheniramine reduces allergic symptoms (sneezing, runny nose, watery eyes) by antagonizing histamine H1 receptors. Dextromethorphan acts centrally in the medulla to suppress the cough reflex. Guaifenesin increases respiratory tract fluid secretions, making mucus less viscous and easier to expectorate. Menthol acts on cold-sensing TRPM8 receptors, providing a cooling sensation.
- Pharmacokinetics:
- Absorption: Chlorpheniramine is well-absorbed orally. Dextromethorphan is also absorbed orally and undergoes first-pass metabolism. Guaifenesin is readily absorbed from the gastrointestinal tract. Menthol is absorbed through the mucous membranes.
- Metabolism: Chlorpheniramine and dextromethorphan are metabolized in the liver, primarily by CYP450 enzymes. Guaifenesin is also metabolized in the liver.
- Elimination: The metabolites of chlorpheniramine, dextromethorphan, and guaifenesin are primarily excreted in urine. Menthol is mainly excreted in urine and feces.
- Mode of Action: Chlorpheniramine competes with histamine for H1 receptor sites. Dextromethorphan acts centrally on sigma opioid receptors and NMDA glutamate receptors in the cough center. Guaifenesin may stimulate gastric vagal receptors, indirectly increasing respiratory tract secretions. Menthol activates TRPM8 receptors.
- Elimination Pathways: Primarily renal excretion for all components after hepatic metabolism.
Dosage
Standard Dosage
Adults:
- Adults and children 12 years and older: One to two teaspoonfuls (5-10 mL) every 4-6 hours.
- Do not exceed four doses in a 24-hour period.
Children:
- 6 to 12 years: One teaspoonful (5 mL) every 4-6 hours, not to exceed four doses in a 24 hours.
- The combination is not recommended for children under 6 years of age.
- Always consult a pediatrician for appropriate dosing in children.
Special Cases:
- Elderly Patients: Use with caution; start with lower doses due to potential for increased sensitivity to side effects.
- Patients with Renal Impairment: Use with caution. Dose adjustment may be necessary.
- Patients with Hepatic Dysfunction: Use with caution. Dose adjustment may be necessary.
- Patients with Comorbid Conditions: Use with caution in patients with asthma, COPD, glaucoma, hypertension, cardiovascular disease, hyperthyroidism, diabetes, or prostatic hypertrophy. Consult a physician for appropriate dosage modifications.
Clinical Use Cases
The combination is generally not indicated for use in clinical settings like intubation, surgical procedures, mechanical ventilation, or ICU care. Its primary use is for symptomatic relief of cough and cold in outpatient settings.
Dosage Adjustments
Dose adjustments are based on age, renal function, and hepatic function. Consult a physician for specific recommendations.
Side Effects
Common Side Effects
- Drowsiness
- Dizziness
- Dry mouth, nose, and throat
- Nausea
- Vomiting
- Headache
- Blurred vision
- Constipation
- Restlessness
- Nervousness
Rare but Serious Side Effects
- Allergic reactions (rash, itching, swelling, severe dizziness, trouble breathing)
- Seizures
- Hallucinations
- Irregular heartbeat
Long-Term Effects
Chronic complications from prolonged use are rare but may include tolerance to dextromethorphan’s cough-suppressing effects.
Adverse Drug Reactions (ADR)
Clinically significant ADRs are rare but may include severe allergic reactions, respiratory depression, and cardiac arrhythmias.
Contraindications
- Hypersensitivity to any component of the combination.
- Concurrent use of MAOIs (monoamine oxidase inhibitors) or within two weeks of discontinuing MAOIs.
- Narrow-angle glaucoma, urinary retention, peptic ulcer, and severe asthma.
Drug Interactions
- MAOIs
- Alcohol
- Other CNS depressants (e.g., sedatives, hypnotics, opioids)
- Antihistamines
- Tricyclic antidepressants
- Anticholinergics
- Medications that prolong the QT interval
Pregnancy and Breastfeeding
- Pregnancy: Use only if clearly needed and under the supervision of a physician.
- Breastfeeding: Chlorpheniramine and dextromethorphan may pass into breast milk. Use with caution and only if the potential benefits outweigh the risks to the infant.
Drug Profile Summary
As provided above.
Popular Combinations
- Often combined with other medications like phenylephrine (decongestant) or acetaminophen (analgesic/antipyretic).
Precautions
As provided above.
FAQs (Frequently Asked Questions)
Q1: What is the recommended dosage for Chlorpheniramine Maleate + Dextromethorphan Hydrobromide + Guaifenesin + Menthol?
A: As described in the Dosage section above. As of today (2025-02-16), the dosage for adults and children 12 years and older is 5-10 mL every four to six hours, not exceeding four doses daily. Children aged 6 to 12 years can have 5mL every four to six hours, also not exceeding four doses per day. It’s important to consult a healthcare provider to confirm the correct dosage, as guidelines may change over time and depending on the individual clinical presentation.
Q2: Can this combination be used in children under 6 years of age?
A: It is generally not recommended for children under 6 unless specifically prescribed by a doctor.
Q3: What are the common side effects?
A: Common side effects include drowsiness, dizziness, dry mouth, nausea, and vomiting.
Q4: Are there any serious side effects?
A: Rare but serious side effects include allergic reactions, seizures, hallucinations, and irregular heartbeat.
Q5: Can I take this medication if I am pregnant or breastfeeding?
A: Consult your doctor before using this medication if you are pregnant or breastfeeding.
Q6: Can I drink alcohol while taking this medication?
A: Alcohol can increase the risk of side effects like drowsiness and dizziness and may interact with dextromethorphan. Avoid alcohol while using this medicine.
Q7: What should I do if I miss a dose?
A: Take the missed dose as soon as you remember. If it is almost time for the next dose, skip the missed dose and take the next scheduled dose. Do not double the dose to catch up.
Q8: Are there any drug interactions I should be aware of?
A: Yes, this combination can interact with various medications, including MAOIs, alcohol, other CNS depressants, and certain antidepressants. Inform your doctor about all other medications you are taking.
Q9: Can I drive or operate machinery while taking this medication?
A: Use caution when driving or operating machinery, as this medication can cause drowsiness and dizziness.
Q10: How should I store this medication?
A: Store in a cool, dry place, away from direct sunlight and out of the reach of children.
