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- What is fexofenadine and pseudoephedrine, and how does it work (mechanism of action)?
- What brand names are available for fexofenadine and pseudoephedrine?
- Is fexofenadine and pseudoephedrine available as a generic drug?
- Do I need a prescription for fexofenadine and pseudoephedrine?
- What are the side effects of fexofenadine and pseudoephedrine?
- What is the dosage for fexofenadine and pseudoephedrine?
- Which drugs or supplements interact with fexofenadine and pseudoephedrine?
- Is fexofenadine and pseudoephedrine safe to take if I'm pregnant or breastfeeding?
- What else should I know about fexofenadine and pseudoephedrine?
What is fexofenadine and pseudoephedrine, and how does it work (mechanism of action)?
Allegra-D is a combination of an antihistamine (fexofenadine) and a decongestant (pseudoephedrine). Fexofenadine is an oral, "second generation" antihistamine that is used to treat the signs and symptoms of allergy and hives. It is similar to the other second generation antihistamines loratadine (Claritin), cetirizine (Zyrtec) and azelastine (Astelin). Histamine is a chemical that is responsible for many of the signs and symptoms of allergic reactions, for example, swelling of the lining of the nose, sneezing, and itchy eyes. Histamine is released from histamine-storing cells (mast cells) and then attaches to other cells that have receptors for histamine. The attachment of the histamine to the receptors causes the cell to become "activated," releasing other chemicals that produce the effects that we associate with allergy (for example, sneezing). Fexofenadine blocks one type of receptor for histamine (the H1 receptor) and thus prevents activation of H1 receptor-containing cells by histamine. Unlike the first generation antihistamines, fexofenadine and other second-generation antihistamines do not readily enter the brain from the blood. Therefore, they cause less drowsiness and are called non-sedating antihistamines. Pseudoephedrine causes blood vessels in the nasal passages to narrow (vasoconstrict). Vasoconstriction reduces nasal congestion by preventing fluid from draining from blood vessels into nasal passages. The FDA approved Allegra-D in December 1997.
What brand names are available for fexofenadine and pseudoephedrine?
Is fexofenadine and pseudoephedrine available as a generic drug?
GENERIC AVAILABLE: Yes
Do I need a prescription for fexofenadine and pseudoephedrine?
What are the side effects of fexofenadine and pseudoephedrine?
Side effects of Allegra-D include stimulation of the nervous system by pseudoephedrine leading to:
- tremor, hallucinations, and
- convulsions (seizures).
Other important side effects include:
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