Nurses Compass
Drug Guide
Cetirizine Hydrochloride and Pseudoephedrine Hydrochloride
Classification
Therapeutic: Nasal Decongestant and Antihistamine combination
Pharmacological: Antihistamine (cetirizine), Sympathomimetic decongestant (pseudoephedrine)
FDA Approved Indications
- Relief of nasal congestion, sneezing, runny nose, and watery eyes due to allergies or hay fever
Mechanism of Action
Cetirizine is a selective peripheral H1 antihistamine that inhibits the effects of histamine at H1 receptor sites, reducing allergy symptoms. Pseudoephedrine is a sympathomimetic agent that constricts blood vessels in the nasal mucosa, leading to decreased swelling and congestion.
Dosage and Administration
Adult: Typically, 5 mg cetirizine + 120 mg pseudoephedrine every 12 hours as needed. Adjust based on response and tolerability.
Pediatric: Not generally recommended for children under 12. For older children, dose adjustments should be made according to pediatric guidelines.
Geriatric: Use with caution; consider starting at lower doses due to potential increased sensitivity.
Renal Impairment: Adjust dose in patients with severe renal impairment; consult specific guidelines.
Hepatic Impairment: Use with caution; no specific dose adjustment recommended but monitor closely.
Pharmacokinetics
Absorption: Both drugs are well absorbed from the gastrointestinal tract.
Distribution: Cetirizine is extensively bound to plasma proteins; pseudoephedrine has minimal protein binding.
Metabolism: Cetirizine undergoes minimal hepatic metabolism; pseudoephedrine undergoes negligible hepatic metabolism.
Excretion: Primarily via urine for both drugs; pseudoephedrine also excreted unchanged.
Half Life: Cetirizine: approximately 8 hours; Pseudoephedrine: approximately 4-6 hours.
Contraindications
- Known hypersensitivity to cetirizine, pseudoephedrine, or any component of the formulation.
Precautions
- Use with caution in patients with hypertension, cardiovascular disease, hyperthyroidism, or increased intraocular pressure. Avoid in children under 12 without medical advice.
Adverse Reactions - Common
- Dry mouth (Common)
- Drowsiness or sedation (Less common)
- Insomnia (Less common)
Adverse Reactions - Serious
- Increased blood pressure, tachycardia (Rare)
- Jaundice, allergic reactions, including anaphylaxis (Rare)
Drug-Drug Interactions
- MAO inhibitors may enhance pseudoephedrine effects, increasing risk of hypertensive crisis.
- Other antihypertensives or CNS depressants may have additive effects.
Drug-Food Interactions
N/ADrug-Herb Interactions
N/ANursing Implications
Assessment: Monitor for effectiveness (relief of allergy symptoms, reduction in nasal congestion) and adverse effects (drowsiness, hypertension).
Diagnoses:
- Ineffective airway clearance related to nasal congestion.
- Risk for decreased cardiac output related to increased blood pressure.
Implementation: Administer with or without food. Educate patient to avoid activities requiring mental alertness until response is known.
Evaluation: Assess symptom relief and monitor for adverse reactions.
Patient/Family Teaching
- Advise patients to avoid excessive alcohol and CNS depressants.
- Instruct on proper timing and dosing.
- Explain potential side effects such as drowsiness or increased blood pressure.
Special Considerations
Black Box Warnings:
- Pseudoephedrine may increase blood pressure and heart rate; use cautiously in hypertensive patients.
Genetic Factors: Consider genetic variations affecting metabolism, especially in poor metabolizers of pseudoephedrine.
Lab Test Interference: None known.
Overdose Management
Signs/Symptoms: Seizures, hallucinations, severe hypertension, CNS stimulation, drowsiness, coma.
Treatment: Supportive care, symptomatic treatment, activated charcoal if ingestion was recent. In cases of severe hypertension, appropriate antihypertensive therapy may be necessary.
Storage and Handling
Storage: Store at room temperature, away from moisture, light, and heat.
Stability: Stable under recommended storage conditions for shelf life.