Is Levocetirizine Less Sedating Than Cetirizine?

Phase 4

Completed

Brief Summary: The purpose of this study is to determine whether cetirizine (zyrtec), levocetirizine (xyzal), and placebo differ in the degree of sedation they produce and their relief of allergy symptoms.

Detailed Description: Levocetirizine, the R-enantiomer of cetirizine, has been found to be less sedating relative to placebo than was cetirizine in separate trials. We plan to examine whether patients who did not tolerate cetirizine due to sedation are able to tolerate levocetirizine. This study will utilize a randomized, double-blind, placebo controlled trial comparing levocetirizine, cetirizine, and placebo in regards to sedation and allergy symptom scores. Each patient will receive levocetirizine, cetirizine, and placebo in randomized order and thus serve as their own control.

Recruitment & Eligibility

Inclusion Criteria

patients 18 years of age or older
patients with perennial allergic rhinitis sensitized (positive RAST within the last 3 years or wheal greater than or equal to 3 mm within the last 3 years) to either:
- dust mite
- cat (if they own an indoor cat)
- dog (if they own an indoor dog)
will allow for sensitization to tree, grass, or weed pollen, cockroach, or mold
history of reported sedation/somnolence when taking cetirizine
patient must have taken cetirizine for at least 1 week prior to discontinuing it
patients must have either tolerated levocetirizine in the past or have never tried levocetirizine.

Exclusion Criteria

chronic urticaria requiring ongoing antihistamine or steroid treatment
atopic dermatitis requiring ongoing antihistamine or steroid treatment
URI or sinus infection during the 2 weeks preceding the beginning of the study
vasomotor (non-allergic) or irritant rhinitis
afrin use
elderly or over 77 years of age (could affect creatinine clearance) or chronic renal insufficiency
patients who have not tolerated levocetirizine in the past due to sedation.
taking other prescription or over the counter antihistamines and unwilling to stop them during the study
the presence of a sleep disorder such as sleep apnea or narcolepsy
the use of as needed sleeping aid medication
the presence of other chronic medical conditions which in the opinion of the investigator would prevent the subject from being able to participate effectively

Arm && Interventions

Group	Intervention	Description
Levocetirzine	Levocetirizine	5 mg daily x 7 days (note = cross over = all participants receive active comparators and placebo)
cetirizine	Cetirizine	10 mg daily x 7 days. Note = crossover study, so all participants recieve all active comparators and placebo.
placebo	Placebo	one tablet daily x 7 days; note that this is a crossover study so all participants receive all active comparators and placebo

Primary Outcome Measures

Name	Time	Method
Modified Epworth Sleepiness Scale	36 days of the study	Epworth Sleepiness Scale ratings (0 to 24); higher scores = increased sedation. This was measured over the 36 days of the study (at the end of each washout period and each intervention period); measured on days 5, 12, 17, 24, 29, and 36. This was mean data for all interventions.
Likert Score Rating Global Sedation	duration of study (36 days)	Likert score range 1 to 9 (no sedation to extreme sedation). Highers scores indicate increased sedation. This was measured on days days 5, 12, 17, 24, 29, and 36 of the study. This was mean data for all interventions.

Secondary Outcome Measures

Name	Time	Method
Total Four Symptom Scores (Allergy Symptoms)	same as primary outcome measure (obtain on days 5, 12, 17, 24, 29, and 36)	Total Four Symptom Scores (TFSS) ranging 0 to 12. Increased scores indicate increased symptoms. This was measured on days 5, 12, 17, 24, 29, and 36 of the study. The mean TFSS for patients receiving placebo, cetirizine, and levocetirizine was then calculated. This was mean data for all interventions.