Statistically significant reductions in symptom scores were observed following the first 60 mg dose, with the effect maintained throughout the 12-hour interval. Each tablet contains 30, 60, or 180 mg fexofenadine hydrochloride (depending on the dosage strength) and the following excipients: croscarmellose sodium, magnesium stearate, microcrystalline cellulose, and pregelatinized starch.
Following oral administration of a 30 mg dose of ALLEGRA Oral Suspension to healthy adult subjects, the mean Cmax was 118.0 ng/mL and occurred at approximately 1.0 hour. In 1 clinical trial conducted with ALLEGRA 60 mg capsules, and in 1 clinical trial conducted with ALLEGRA-D 12 Hour extended release tablets, onset of action was seen within 1 to 3 hours. In three 2-week, multicenter, randomized, double-blind, placebo-controlled trials in subjects 12 to 68 years of age with seasonal allergic rhinitis (n=1634), fexofenadine hydrochloride 60 mg twice daily significantly reduced total symptom scores (the sum of the individual scores for sneezing, rhinorrhea, itchy nose/palate/throat, itchy/watery/red eyes) compared to placebo. Fexofenadine hydrochloride was rapidly absorbed following oral administration of a single dose of two 60 mg capsules to healthy male subjects Allegra D - Substitute a mean time to maximum plasma Allegra D - Substitute occurring at 2.6 hours post-dose. Pharmacokinetics in renally and hepatically impaired subjects and geriatric subjects, obtained after a single dose of 80 mg fexofenadine hydrochloride, were compared to those from healthy subjects in a separate study of similar design. Onset of action for reduction in total symptom scores, excluding nasal congestion, was observed at 60 minutes compared to placebo following a single 60 mg fexofenadine hydrochloride dose administered to subjects with seasonal allergic rhinitis who were exposed to ragweed pollen in an environmental exposure unit. Improvement was demonstrated within 1 day of treatment with fexofenadine hydrochloride 180 mg and was maintained over the entire 4- week treatment period. Co-administration of 180 mg fexofenadine hydrochloride tablet with a high fat meal decreased the mean area under the curve (AUC) and (Cmax) of fexofenadine by 21 and 20% respectively. Similar reductions were observed for mean number of wheals and mean pruritus score at the end of the 24-hour dosing interval. There were no significant differences in the effect of fexofenadine hydrochloride across subgroups of subjects defined by gender, age, weight, and race. ALLEGRA Oral Suspension, a white uniform suspension, contains 6 mg fexofenadine hydrochloride per mL and the following excipients: propylene glycol, edetate disodium, propylparaben, butylparaben, xanthan gum, poloxamer 407, titanium dioxide, sodium phosphate monobasic monohydrate, sodium phosphate dibasic heptahydrate, artificial raspberry cream flavor, Allegra D - Substitute xylitol and purified water. The 60 mg twice daily dose did not provide any additional benefit over the 30 mg twice daily dose in pediatric subjects 6 to 11 years of age. ALLEGRA is formulated as a tablet for oral administration. Fexofenadine hydrochloride inhibited antigen-induced bronchospasm in sensitized guinea pigs and histamine release from peritoneal mast cells in rats. In 1 of these 2 studies, conducted in 411 pediatric subjects, all 3 doses of fexofenadine hydrochloride significantly reduced total symptom scores (the sum of the individual scores for sneezing, rhinorrhea, itchy nose/palate/throat, itchy/watery/red eyes) compared to placebo, however, a dose-response relationship was not seen.
In vivo animal studies also suggest that in addition to enhancing absorption, ketoconazole decreases fexofenadine gastrointestinal secretion, while erythromycin may also decrease Zyrtec Clartin Allegra excretion. Fexofenadine hydrochloride is a white to off-white crystalline powder.