What is Levocetirizine (Xyzal), an antihistamine?

From the Guidelines

Levocetirizine is recommended for patients with persistent allergic rhinitis and concomitant asthma, as it has been shown to decrease symptoms and improve quality of life. According to the European Position Paper on Rhinosinusitis and Nasal Polyps 2007, a study published in the journal Rhinology in 2007 1, levocetirizine has been found to be effective in reducing symptoms and improving quality of life in patients with persistent allergic rhinitis and asthma. The study highlights that treatment with levocetirizine decreased both symptoms and improved quality of life, as measured by the Rhinasthma questionnaire, in patients with persistent allergic rhinitis and asthma.

Some key points to consider when prescribing levocetirizine include:

• The medication is a second-generation antihistamine, which means it causes less drowsiness compared to first-generation antihistamines
• The standard adult dose is 5 mg taken once daily in the evening
• Patients with kidney impairment may need dose adjustments
• Common side effects include mild drowsiness, dry mouth, and fatigue
• The medication should be taken at the same time each day for best results, and patients should avoid alcohol while using it as this can increase drowsiness

It's also important to note that prolonged therapy with levocetirizine over 6 months can reduce co-morbidities, including asthma, in patients with persistent allergic rhinitis and improve rhinitis-specific quality of life, as reported in the same study 1. Overall, levocetirizine is a valuable treatment option for patients with persistent allergic rhinitis and concomitant asthma, and its use can lead to improved symptoms and quality of life.

From the FDA Drug Label

PRINCIPAL DISPLAY PANEL Levocetirizine Dihydrochloride Tablets USP 5 mg-35's Container carton Compare to XYZAL® Allergy 24HR Active Ingredient* Allergy Relief Levocetirizine Dihydrochloride Tablets, USP 5 mg Antihistamine 24 HOUR Relief of Sneezing Runny Nose Itchy Nose or Throat Itchy, Watery Eyes Original Prescription Strength 35 TABLETS ACTIVE INGREDIENT(S) Levocetirizine dihydrochloride USP 5 mg DO NOT USE • if you have kidney disease • if you have ever had an allergic reaction to this product or any of its ingredients or to an antihistamine containing cetirizine

The main use of Levocetirizine is for allergy relief, providing 24-hour relief of symptoms such as:

• Sneezing
• Runny Nose
• Itchy Nose or Throat
• Itchy, Watery Eyes It is an antihistamine and its active ingredient is Levocetirizine dihydrochloride USP 5 mg 2, 2. Contraindications include kidney disease and previous allergic reactions to the product or its ingredients, or to antihistamines containing cetirizine 2.

From the Research

Overview of Levocetirizine

• Levocetirizine is a selective, potent, oral histamine H(1) receptor antagonist used for the symptomatic treatment of allergic rhinitis and chronic idiopathic urticaria 3.
• It has been shown to be effective in reducing symptoms of seasonal allergic rhinitis (SAR) in several studies 4, 5.

Efficacy in Seasonal Allergic Rhinitis

• A study published in 2001 found that levocetirizine was significantly superior to placebo in reducing the mean Total Four-Symptom Score (T4SS) over a 2-week period in patients with SAR 4.
• Another study published in 2010 found that levocetirizine resulted in significantly greater improvement from baseline vs placebo in the 24-hour reflective Total 5-Symptom Score (T5SS) during the entire treatment period in US adults with SAR 5.
• However, a study published in 2010 found that levocetirizine failed to show significant efficacy compared with placebo in a US adult population with SAR, which is inconsistent with all previous studies with levocetirizine 6.

Safety and Tolerability

• Levocetirizine has been shown to be well tolerated in several studies, with a low incidence of adverse events 4, 5, 6.
• The most common adverse events reported with levocetirizine include somnolence and fatigue 5, 6.
• A study published in 2004 found that cetirizine, the racemic mixture of which levocetirizine is a part, was well tolerated in adults, adolescents, and pediatric patients with allergic disorders, with a low incidence of somnolence and no adverse effects on cognitive function 7.

Comparison with Other Antihistamines

• A study published in 2006 found that levocetirizine had better efficacy than desloratadine, loratadine, or fexofenadine in allergen challenge chamber studies 3.
• A study published in 2004 found that cetirizine was as effective as other H1 receptor antagonists, including ebastine, fexofenadine, loratadine, and mizolastine, in the treatment of SAR and CIU 7.