Xyzal (levocetirizine dihydrochloride) represents a significant advancement in second-generation antihistamine therapy, offering patients and healthcare providers a potent, selective histamine H1-receptor antagonist with demonstrated efficacy in managing allergic conditions. This prescription medication provides 24-hour relief from symptoms associated with perennial and seasonal allergic rhinitis, as well as chronic idiopathic urticaria. Developed through enantioselective purification of cetirizine, Xyzal delivers the pharmacologically active R-enantiomer, resulting in enhanced receptor binding affinity and improved therapeutic profile while maintaining the favorable safety characteristics of its predecessor. Clinical studies have established its rapid onset of action, with significant symptom reduction observed within one hour of administration in adult populations.

Features

• Contains levocetirizine dihydrochloride 5 mg per tablet
• Second-generation, non-sedating antihistamine classification
• Selective peripheral H1-receptor antagonist mechanism
• 24-hour duration of action with once-daily dosing
• Rapid onset of action (within 60 minutes in most patients)
• Minimal cytochrome P450 metabolism (primarily renally excreted unchanged)
• Bioavailability of approximately 85% with oral administration
• Linear pharmacokinetics across therapeutic dose range
• Tablet formulation with film coating for ease of swallowing
• Demonstrated efficacy in both adult and pediatric populations (6 years and older)

Benefits

• Provides comprehensive 24-hour relief from allergic rhinitis symptoms including rhinorrhea, sneezing, nasal congestion, and ocular manifestations
• Effectively manages pruritus and reduces wheal formation in chronic idiopathic urticaria
• Maintains alertness and cognitive function with minimal central nervous system penetration
• Offers consistent symptom control with once-daily dosing convenience
• Demonstrates favorable safety profile with low incidence of anticholinergic effects
• Suitable for long-term management of chronic allergic conditions

Common use

Xyzal is primarily indicated for the relief of symptoms associated with seasonal allergic rhinitis in adults and children 6 years of age and older. These symptoms include rhinorrhea, sneezing, nasal pruritus, ocular pruritus, and lacrimation. The medication is equally effective for perennial allergic rhinitis, providing year-round symptom management for indoor allergens such as dust mites, pet dander, and mold spores. Additionally, Xyzal is approved for the treatment of uncomplicated skin manifestations of chronic idiopathic urticaria in adults and children 6 years of age and older, significantly reducing pruritus and hive formation. Off-label uses may include adjunctive therapy in atopic dermatitis and other histamine-mediated conditions, though such applications require physician supervision.

Dosage and direction

The recommended dosage of Xyzal for adults and children 12 years of age and older is 5 mg (one tablet) once daily in the evening. For children 6 to 11 years of age, the recommended dose is 2.5 mg (one-half tablet) once daily in the evening. Administration may be with or without food, though consistent timing is recommended for optimal therapeutic levels. For patients with renal impairment, dosage adjustment is necessary: creatinine clearance of 50-80 mL/min requires 2.5 mg once daily; 30-50 mL/min requires 2.5 mg every other day; 10-30 mL/min requires 2.5 mg twice weekly (every 3-4 days). Not recommended for patients with creatinine clearance less than 10 mL/min or undergoing hemodialysis. Tablets should be swallowed whole with a small amount of water.

Precautions

Patients should be cautioned about engaging in activities requiring mental alertness, such as operating machinery or driving, until they know how Xyzal affects them. Although classified as non-sedating, somnolence has been reported in some patients. Use with caution in patients with predisposing factors for urinary retention (e.g., prostatic hyperplasia, bladder outlet obstruction) due to potential anticholinergic effects. Monitor renal function in elderly patients and those with compromised renal function. Patients with hepatic impairment without renal involvement require no dosage adjustment. Discontinue Xyzal at least 48 hours before skin allergy testing to avoid false negative results. Pregnancy Category B: should be used during pregnancy only if clearly needed. Levocetirizine is excreted in human milk—exercise caution when administering to nursing women.

Contraindications

Xyzal is contraindicated in patients with known hypersensitivity to levocetirizine, cetirizine, hydroxyzine, or any of the inactive ingredients in the formulation. The medication is contraindicated in patients with end-stage renal disease (creatinine clearance <10 mL/min) or those undergoing hemodialysis. Not recommended for use in children under 6 years of age due to limited safety and efficacy data in this population. Contraindicated in patients with rare hereditary problems of galactose intolerance, Lapp lactase deficiency, or glucose-galactose malabsorption due to the lactose content in the tablet formulation.

Possible side effect

The most commonly reported adverse reactions in clinical trials (≥2% and greater than placebo) included somnolence (6% vs 2% placebo), nasopharyngitis (4% vs 2%), fatigue (3% vs 1%), dry mouth (3% vs 1%), and pharyngitis (2% vs 1%). Less common side effects may include headache, dizziness, nausea, abdominal pain, and cough. In pediatric patients 6-12 years, the adverse reaction profile was similar to adults, with headache, somnolence, and pharyngitis being most frequently reported. Rare but serious adverse effects may include hypersensitivity reactions (angioedema, bronchospasm, anaphylaxis), seizures, and hepatitis. Patients should report any persistent or severe side effects to their healthcare provider promptly.

Drug interaction

Formal drug interaction studies have shown no clinically relevant interactions with pseudoephedrine, ketoconazole, azithromycin, or erythromycin. However, concomitant use with CNS depressants (alcohol, benzodiazepines, opioids, sedative-hypnotics) may enhance sedative effects. Theoretical interactions exist with medications that inhibit active renal secretion, though clinical significance remains uncertain. No significant protein binding interactions are expected due to low plasma protein binding (90%). Theophylline may decrease levocetirizine clearance by approximately 16%, though dosage adjustment is generally not required. Monitor patients when co-administering with other renally excreted drugs.

Missed dose

If a dose is missed, it should be taken as soon as remembered unless it is almost time for the next scheduled dose. In such cases, skip the missed dose and resume the regular dosing schedule. Patients should not double the dose to make up for a missed administration. Consistent daily dosing is recommended for optimal therapeutic effect, particularly for management of chronic conditions. Establishing a routine (e.g., evening administration) can help improve adherence and minimize missed doses.

Overdose

In case of overdose, symptoms may include somnolence, agitation, restlessness, and tachycardia in adults. Children may demonstrate initially agitation and restlessness followed by drowsiness. There is no specific antidote for levocetirizine overdose. Treatment should be supportive and symptomatic, including gastric lavage if presented within one hour of ingestion. Hemodialysis is ineffective due to high protein binding and volume of distribution. Monitor vital signs and provide appropriate supportive care. Contact a poison control center for latest guidance on management.

Storage

Store Xyzal tablets at controlled room temperature 20°-25°C (68°-77°F) with excursions permitted between 15°-30°C (59°-86°F). Keep in the original blister packaging to protect from moisture and light. Keep out of reach of children and pets. Do not use beyond the expiration date printed on the packaging. Properly discard any unused medication through medication take-back programs or according to FDA-recommended disposal methods. Do not flush medications down the toilet unless specifically instructed to do so.

Disclaimer

This information is provided for educational purposes only and does not constitute medical advice. Individual patient responses to medication may vary. Healthcare providers should exercise professional judgment when prescribing Xyzal, considering individual patient factors, contraindications, and potential adverse effects. Patients should consult with their healthcare provider before starting, stopping, or changing any medication regimen. Full prescribing information should be reviewed before administration. The efficacy and safety data presented are based on clinical trials and post-marketing surveillance.

Reviews

Clinical studies demonstrate that Xyzal provides effective relief for allergic rhinitis symptoms with 60% of patients experiencing significant improvement within the first week of treatment. In chronic idiopathic urticaria trials, Xyzal reduced pruritus severity scores by 50% compared to placebo after 4 weeks of treatment. Patient satisfaction surveys indicate high rates of continued use, with 78% of patients reporting improved quality of life measures related to allergy symptoms. Healthcare providers appreciate the predictable pharmacokinetics and favorable drug interaction profile. Real-world evidence supports the maintained efficacy seen in clinical trials, with particular benefit noted in patients who previously experienced sedation with other antihistamines.