Usage
This combination medication is prescribed for the symptomatic relief of common cold, flu, and allergy symptoms, particularly dry cough, nasal congestion, runny nose, sneezing, and watery eyes.
Pharmacological Classification:
This drug combines three classes of medications:
- Cetirizine: Antihistamine (H1-receptor antagonist)
- Dextromethorphan Hydrobromide: Cough suppressant (Antitussive)
- Phenylephrine: Decongestant (Alpha-1 adrenergic agonist)
Mechanism of Action:
- Cetirizine: Blocks the action of histamine, reducing allergy symptoms.
- Dextromethorphan: Suppresses the cough reflex by affecting the cough center in the brain.
- Phenylephrine: Constricts blood vessels in the nasal passages, reducing swelling and congestion.
Alternate Names
There are no officially recognized alternate names for this specific combination. However, each individual drug has its own synonyms. The combination may be referred to simply as “Cetirizine-Dextromethorphan-Phenylephrine.”
Brand Names: A number of brand names exist for this combination, depending on the manufacturer and region. Some examples include Kozifed Plus and Galirex.
How It Works
Pharmacodynamics:
- Cetirizine: Reduces vascular permeability, decreasing edema and inflammation associated with allergic reactions.
- Dextromethorphan: Acts centrally on the medulla oblongata to elevate the cough threshold.
- Phenylephrine: Causes vasoconstriction in the nasal mucosa, reducing congestion.
Pharmacokinetics:
- Cetirizine: Well absorbed orally. Peak plasma concentrations reached in approximately 1 hour. Primarily excreted unchanged in urine.
- Dextromethorphan: Readily absorbed from the gastrointestinal tract. Extensively metabolized in the liver, primarily by CYP2D6. Excreted in urine as metabolites.
- Phenylephrine: Poorly absorbed orally. Metabolized in the liver and intestinal wall by monoamine oxidase. Excreted in urine.
Mode of Action:
- Cetirizine: Competitively inhibits histamine binding to H1 receptors.
- Dextromethorphan: NMDA receptor antagonist (at high doses), sigma-1 receptor agonist.
- Phenylephrine: Alpha-1 adrenergic receptor agonist.
Elimination Pathways:
- Cetirizine: Primarily renal excretion.
- Dextromethorphan: Hepatic metabolism, renal excretion of metabolites.
- Phenylephrine: Hepatic metabolism, renal excretion.
Dosage
Standard Dosage
Children: Dosage is dependent on age and weight, and should be carefully determined by a physician. Not recommended for children under 2 years of age.
Special Cases:
- Elderly Patients: Dosage adjustments may be necessary due to potential age-related decline in renal or hepatic function.
- Patients with Renal Impairment: Dose reduction may be required based on the degree of impairment.
- Patients with Hepatic Dysfunction: Dosage adjustment should be considered due to potential changes in drug metabolism.
- Patients with Comorbid Conditions: Careful consideration of potential drug interactions and exacerbation of existing conditions is necessary.
Clinical Use Cases
This combination medication is not typically used in clinical settings such as intubation, surgical procedures, mechanical ventilation, or the ICU. It is primarily intended for outpatient management of common cold and allergy symptoms.
Dosage Adjustments
Dosage adjustments should be made on a case-by-case basis, considering patient-specific factors such as renal function, hepatic function, and other comorbidities.
Side Effects
Common Side Effects
Drowsiness, dizziness, dry mouth, nausea, headache, blurred vision, and constipation.
Rare but Serious Side Effects
Allergic reactions (rash, itching, swelling), difficulty breathing, hallucinations, seizures, rapid or irregular heartbeat.
Long-Term Effects
Chronic use of phenylephrine can lead to rebound congestion.
Adverse Drug Reactions (ADR)
Severe allergic reactions (anaphylaxis), serotonin syndrome (with concurrent use of MAOIs or other serotonergic drugs), cardiac arrhythmias.
Contraindications
Hypersensitivity to any component of the medication, concurrent use of MAOIs, severe hypertension, coronary artery disease, closed-angle glaucoma, urinary retention, severe liver or kidney disease.
Drug Interactions
MAOIs, antidepressants (tricyclics, SSRIs), other antihistamines, decongestants, alcohol, sedatives, and some antifungal medications.
Pregnancy and Breastfeeding
The safety of this combination during pregnancy and breastfeeding has not been fully established. Use only if clearly needed and under the supervision of a physician.
Drug Profile Summary
- Mechanism of Action: Antihistamine, cough suppressant, and decongestant.
- Side Effects: Drowsiness, dizziness, dry mouth, nausea, headache.
- Contraindications: Hypersensitivity, MAOI use, severe cardiovascular disease, closed-angle glaucoma.
- Drug Interactions: MAOIs, antidepressants, other antihistamines, decongestants, alcohol.
- Pregnancy & Breastfeeding: Consult a physician.
- Dosage: Varies based on age and condition; see detailed dosage section.
- Monitoring Parameters: Blood pressure, heart rate, respiratory status.
Popular Combinations
Often combined with analgesics/antipyretics like paracetamol or ibuprofen for additional relief of cold and flu symptoms.
Precautions
Use with caution in patients with hypertension, heart disease, diabetes, thyroid disorders, glaucoma, and prostatic hypertrophy. Avoid alcohol and operating heavy machinery.
FAQs (Frequently Asked Questions)
Q1: What is the recommended dosage for Cetirizine + Dextromethorphan Hydrobromide + Phenylephrine?
A: The dosage varies depending on the age and condition of the patient. Adults typically take 5-10 ml every 4-6 hours, not exceeding 6 doses per day. Pediatric dosages should be determined by a physician.
Q2: Can this medication be used in children under 2 years of age?
A: No, it is generally not recommended for children under 2 years old.
Q3: What are the common side effects?
A: Common side effects include drowsiness, dizziness, dry mouth, nausea, and headache.
Q4: Can I drive while taking this medication?
A: Use caution as it may cause drowsiness or dizziness. Avoid driving if you experience these effects.
Q5: What should I do if I miss a dose?
A: Take the missed dose as soon as you remember. If it is near the time of the next dose, skip the missed dose and continue with your regular schedule.
Q6: Can I take this medication with alcohol?
A: Alcohol should be avoided as it can increase the risk of drowsiness and other side effects.
Q7: What are the serious side effects to watch out for?
A: Serious side effects include allergic reactions, difficulty breathing, hallucinations, seizures, and rapid or irregular heartbeat. Seek immediate medical attention if these occur.
Q8: Is this medication safe during pregnancy or breastfeeding?
A: Consult a physician before using this medication during pregnancy or breastfeeding. The safety profile is not fully established.
Q9: Can this medication interact with other medications I’m taking?
A: Yes, it can interact with several medications including MAOIs, antidepressants, and other antihistamines. Inform your physician about all other medications you are taking.
Q10: Can this medication cause rebound congestion?
A: Chronic use of the phenylephrine component can lead to rebound congestion. Use as directed and consult your physician if congestion persists.
