Usage
Chlorpheniramine maleate + pseudoephedrine is prescribed for the temporary relief of symptoms associated with the common cold, hay fever, and other upper respiratory allergies. These symptoms include nasal congestion, runny nose, sneezing, itchy or watery eyes, and itching of the nose or throat.
Pharmacological Classification: This combination drug falls under two classifications:
- Antihistamine (Chlorpheniramine): Reduces allergy symptoms by blocking the effects of histamine.
- Decongestant (Pseudoephedrine): Relieves nasal congestion by constricting blood vessels in the nasal passages.
Alternate Names
While a common international nonproprietary name (INN) isn’t established, regional or descriptive names might exist. Brand names include Allerest Maximum Strength and Hay Fever, Sudafed Sinus and Allergy, and various generic formulations.
How It Works
Pharmacodynamics:
Chlorpheniramine, a first-generation alkylamine H1-receptor antagonist, competes with histamine for receptor sites, thus reducing the effects of histamine release, which include vasodilation, increased capillary permeability, and smooth muscle contraction. Pseudoephedrine, a sympathomimetic amine, acts as an alpha-adrenergic receptor agonist, primarily in the respiratory tract. This leads to vasoconstriction, shrinking the swollen nasal mucous membranes and reducing nasal congestion.
Pharmacokinetics:
Both chlorpheniramine and pseudoephedrine are well-absorbed orally. Chlorpheniramine is metabolized in the liver via CYP450 enzymes, primarily CYP2D6, and eliminated renally. Pseudoephedrine is partially metabolized in the liver and excreted primarily unchanged in the urine.
Mode of Action:
- Chlorpheniramine: H1 receptor antagonism.
- Pseudoephedrine: Alpha-adrenergic receptor agonism.
Dosage
Standard Dosage
Adults:
One tablet (chlorpheniramine maleate 4 mg + pseudoephedrine HCl 60 mg) every 4 to 6 hours. Maximum: 4 tablets per 24 hours. Liquid formulations have different concentrations and dosing instructions; always refer to the specific product labeling.
Children:
- <6 years: Consult a pediatrician.
- 6-12 years: Liquid formulations are preferred. Refer to specific product labeling for precise dosing according to age and formulation.
- ≥12 years: Refer to adult dosing.
Special Cases:
- Elderly Patients: Start with a lower dose and monitor for adverse effects.
- Patients with Renal Impairment: Dose adjustment may be necessary.
- Patients with Hepatic Dysfunction: Dose adjustment may be necessary.
- Patients with Comorbid Conditions: Caution is advised in patients with cardiovascular disease, hypertension, diabetes, glaucoma, hyperthyroidism, and prostatic hypertrophy.
Clinical Use Cases
The combination is not typically used in clinical settings like intubation, surgical procedures, mechanical ventilation, or the ICU. Its primary use is for outpatient symptomatic relief of cold and allergy symptoms. For specific situations such as emergency situations or use within hospital settings, consult a clinical pharmacologist.
Side Effects
Common Side Effects:
Drowsiness, dizziness, dry mouth, blurred vision, constipation, and nausea.
Rare but Serious Side Effects:
Allergic reactions (rash, hives, facial swelling), difficulty breathing, hallucinations, seizures, rapid or irregular heartbeat, difficulty urinating.
Long-Term Effects:
Tolerance to the decongestant effect can develop with prolonged use.
Contraindications
Hypersensitivity to chlorpheniramine or pseudoephedrine, severe hypertension or coronary artery disease, narrow-angle glaucoma, MAOI use within 14 days, severe liver or kidney disease.
Drug Interactions
MAOIs, alcohol, other sedatives or tranquilizers, antihypertensives, antidepressants, and other cold or allergy medications.
Pregnancy and Breastfeeding
Consult with a doctor before use during pregnancy or breastfeeding. Use is generally discouraged, especially in the first trimester and while establishing breastfeeding.
Drug Profile Summary
- Mechanism of Action: Antihistamine (H1-receptor antagonist) and decongestant (alpha-adrenergic agonist).
- Side Effects: Drowsiness, dizziness, dry mouth, blurred vision, constipation, nausea. Rarely: allergic reactions, seizures, cardiac arrhythmias.
- Contraindications: Hypersensitivity, severe cardiovascular disease, narrow-angle glaucoma, MAOI use, severe liver/kidney disease.
- Drug Interactions: MAOIs, alcohol, sedatives, antihypertensives, antidepressants, other cold/allergy medications.
- Pregnancy & Breastfeeding: Consult a doctor before use.
- Dosage: Adults: One tablet every 4-6 hours (max 4 tablets/24h). Children: Consult product labeling or pediatrician.
- Monitoring Parameters: Blood pressure, heart rate, respiratory rate, mental status.
Popular Combinations
This combination itself is a popular formulation. However, related combinations may contain additional ingredients like ibuprofen (for pain and fever) or dextromethorphan (for cough suppression).
Precautions
Pre-existing cardiovascular disease, hypertension, diabetes, glaucoma, hyperthyroidism, prostatic hypertrophy. Caution in elderly patients. Avoid alcohol and operating machinery.
FAQs (Frequently Asked Questions)
Q1: What is the recommended dosage for Chlorpheniramine Maleate + Pseudoephedrine?
A: Adults: One tablet (4 mg chlorpheniramine + 60 mg pseudoephedrine) every 4-6 hours, not exceeding 4 tablets/24 hours. Pediatric dosing varies; consult a pediatrician or product label.
Q2: Can I take this medication if I am pregnant or breastfeeding?
A: Consult your doctor before using this medication during pregnancy or breastfeeding. Use, especially during the first trimester and while establishing breastfeeding, is generally discouraged.
Q3: What are the common side effects?
A: Drowsiness, dizziness, dry mouth, blurred vision, constipation, and nausea are common.
Q4: What should I avoid while taking this medication?
A: Alcohol, operating machinery, and other sedating medications.
Q5: Can I take this with other cold or allergy medicines?
A: Consult your doctor or pharmacist before combining with other cold or allergy medications, as they might contain the same ingredients, leading to an overdose.
Q6: Are there any serious side effects I should be aware of?
A: Allergic reactions, breathing difficulties, hallucinations, seizures, and heart rhythm abnormalities are rare but serious potential side effects. Seek immediate medical attention if these occur.
Q7: What conditions might make this medication unsafe for me?
A: Contraindications include hypersensitivity, severe cardiovascular disease, narrow-angle glaucoma, recent MAOI use, and severe liver/kidney disease.
Q8: Does this medication interact with any other drugs?
A: Yes, it interacts with MAOIs, alcohol, sedatives, antihypertensives, antidepressants, and other cold/allergy medications. Always disclose all medications you are taking to your doctor or pharmacist.
A: While chlorpheniramine is not habit-forming, tolerance to the decongestant effect of pseudoephedrine can develop with prolonged use. Avoid prolonged use without consulting a physician.
