However, no additional benefit of the 120 or 240 mg fexofenadine hydrochloride twice daily dose was seen over the 60 mg twice daily dose in reducing symptom scores. A dose of 5 mL of ALLEGRA Oral Suspension containing 30 mg of fexofenadine hydrochloride is bioequivalent to a 30 mg dose of ALLEGRA tablets. The mean elimination half-life of fexofenadine was 14.4 hours following administration of 60 mg twice daily in healthy subjects. Fexofenadine hydrochloride is a white to off-white crystalline powder. Both enantiomers of fexofenadine hydrochloride displayed approximately equipotent antihistaminic effects. Because the absolute bioavailability of fexofenadine hydrochloride has not been established, it is unknown if the fecal component represents primarily unabsorbed drug or the result of biliary excretion. 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. 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. The administration of 30 mg ALLEGRA Oral Suspension with a high fat meal decreased the AUC and the mean Cmax by approximately 30 and 47%, respectively in healthy adult subjects.


There were no significant differences in the effect of fexofenadine hydrochloride across subgroups of subjects defined by gender, age, weight, and race. ALLEGRA is formulated as a tablet for oral administration. Human mass balance studies documented a recovery of approximately 80% and 11% of the [14C] fexofenadine hydrochloride dose in the feces and urine, respectively. The mechanism of these interactions has been evaluated in in vitro, in situ, and in vivo animal models. Fexofenadine hydrochloride inhibited antigen-induced bronchospasm in sensitized guinea pigs and histamine release from peritoneal mast cells in rats. In one 2-week, multicenter, randomized, double-blind clinical trial in subjects 12 to 65 years of age with seasonal allergic rhinitis (n=863), fexofenadine hydrochloride 180 mg once 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. These studies indicate that ketoconazole or erythromycin co-administration What Is Allegra D fexofenadine gastrointestinal absorption.
It is freely soluble in methanol and ethanol, slightly soluble in chloroform and water, and insoluble in hexane.