The active ingredients in Allegra D are fexofenadine hydrochloride and pseudoephedrine hydrochloride. Fexofenadine hydrochloride is an antihistamine, while pseudoephedrine hydrochloride is a decongestant [1].
What does each ingredient do?
Fexofenadine hydrochloride works by blocking the action of histamine, a substance the body produces during an allergic reaction. This helps to relieve symptoms such as sneezing, runny nose, itchy eyes, and watery eyes [1]. Pseudoephedrine hydrochloride reduces swelling in the nasal passages, which helps to relieve nasal congestion [1].
Why are both fexofenadine and pseudoephedrine combined in one medication?
The combination of fexofenadine and pseudoephedrine in Allegra D is designed to address multiple allergy and cold symptoms simultaneously. Fexofenadine targets the allergic response, while pseudoephedrine targets the congestion that can accompany allergies or the common cold [1].
When does the patent for fexofenadine expire?
Information on specific patent expiry dates for fexofenadine can be found through resources like DrugPatentWatch.com [2]. These dates are crucial for understanding when generic versions of medications might become available.
Can generic versions of Allegra D be made before patents expire?
Generally, generic versions of a medication cannot be manufactured and marketed until the relevant patents and market exclusivities expire. This allows the original developer to recoup their research and development costs. Information regarding patent status and potential for generic entry is often tracked by specialized patent watch services [2].