Since that time, it has achieved blockbuster drug status with global sales of US$1.87B in 2004 (with $1.49B coming from the United States). AMRI received royalty payments from Aventis that enabled the growth of AMRI.In January 2011, the FDA approved over-the-counter sales of fexofenadine in the United States, and Sanofi Aventis version became available in March 2011.
Fexofenadine was also shown to inhibit histamine-induced wheal and flare to a significantly greater degree than loratadine or desloratadine, but was slightly less effective than levocetirizine.Fexofenadine at doses above 120 mg a day does not appear to provide additional efficacy in the treatment of allergic rhinitis. Side effects
The most common side effects include headache, back and muscle pain, miosis or pinpoint pupils, nausea, drowsiness, and menstrual cramps. Anxiety and insomnia have also been rarely reported. The most common side effects demonstrated during clinical trials were cough, upper respiratory tract infection, fever, and otitis media for children ages 6 to 11 and fatigue for children ages 6 months to 5 years. Overdose
The safety profile of fexofenadine is quite favorable, as no cardiovascular or sedative effects have been shown to occur even when taking 10 times the recommended dose. Research on humans ranges from a single 800-mg dose, to a twice-daily, 690-mg dose for a month, with no clinically significant adverse effects, when compared to a placebo. No deaths occurred in testing on mice, at 5000 mg/kg body weight, which is 110 times the maximum recommended dose for an adult human. If overdose were to occur, supportive measures are recommended. Theoretically, an overdose could present as dizziness, dry mouth, and/or drowsiness, consistent with an exaggeration of the usual side effects. Hemodialysis does not appear to be an effective means of removing fexofenadine from the blood. Pharmacology
Pharmacodynamics
Fexofenadine is a selective peripheral H1 receptor antagonist.