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from eMedTV.comHow Does Allegra Work?
When you come in contact with something you're allergic to, a chain reaction begins inside your body. During this chain reaction, specialized cells release powerful chemicals. Some of these chemicals can trigger swelling of the nasal passages leading to nasal congestion (a "stuffy nose"). Other chemicals, such as histamine, can cause sneezing, itching, and irritation.Allegra is classified as an antihistamine. Allegra blocks the effects of histamine (hence its classification as an antihistamine). This can relieve allergy symptoms. However, since histamine is not the cause of nasal congestion, Allegra will not help open nasal passages.
Effects of Allegra
Prior to Allegra's approval in the United States, a number of clinical studies were conducted on over 4,500 adults and children to determine the safety and effectiveness of Allegra. These studies analyzed the effects of Allegra on both seasonal allergy symptoms and chronic hives. In these studies, people taking Allegra experienced relief of their symptoms compared to a group of people who did not take the medicine. Allergy relief was measured based on a symptom score that rated changes in the following symptoms:- Sneezing
- Runny nose
- Itchy nose or throat
- Itchy, watery, or red eyes.
Improvement in symptoms was seen between one and three hours after taking Allegra.
For chronic hives, the symptom score measured changes in itching and the number of hives.
Written by/reviewed by: Kristi Monson, PharmD; Arthur Schoenstadt, MD
Last reviewed by: Kristi Monson, PharmD