Does Allegra (fexofenadine) cause side effects?
Allegra (fexofenadine) is an oral, "second generation" antihistamine used to treat seasonal allergies in patients 2 years of age and older and chronic urticaria (hives, itching) in patients 6 months of age and older.
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 cells to be "activated," releasing other chemicals that produce the effects that we associate with allergy (for example, sneezing). Allegra 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, Allegra 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.
Common side effects of Allegra include
Other important side effects of Allegra include
Drug interactions of Allegra include aluminum-containing antacids (for example, Maalox), which reduce the absorption of Allegra when administered 15 minutes apart.
- Therefore, aluminum-containing antacids and Allegra should not be administered together. Fruit juices (apple, orange, grapefruit) may reduce the absorption of Allegra.
- Allegra should only be administered with water.
Allegra has not been adequately studied in pregnant women. Allegra has not been adequately studied in women who are breastfeeding. Consult your doctor before breastfeeding.
What are the important side effects of Allegra (fexofenadine)?
The most common side effects of fexofenadine are:
Other important side effects include:
Allegra (fexofenadine) is an oral, "second generation" antihistamine used to treat seasonal allergies in patients 2 years of age and older and chronic urticaria (hives, itching) in patients 6 months of age and older. Common side effects of Allegra include headache, diarrhea, nausea, vomiting, weakness, sleepiness, and dizziness. Allegra has not been adequately studied in pregnant women. Allegra has not been adequately studied in women who are breastfeeding.
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Related Disease Conditions
An allergy refers to a misguided reaction by our immune system in response to bodily contact with certain foreign substances. When these allergens come in contact with the body, it causes the immune system to develop an allergic reaction in people who are allergic to it. It is estimated that 50 million North Americans are affected by allergic conditions. The parts of the body that are prone to react to allergies include the eyes, nose, lungs, skin, and stomach. Common allergic disorders include hay fever, asthma, allergic eyes, allergic eczema, hives, and allergic shock.
Fragrances and preservatives in cosmetics may cause allergic reactions in some people. Symptoms include redness, itching, and swelling after the product comes in contact with the person's skin. Treatment typically involves the use of over-the-counter cortisone creams.
Insect Sting Allergies
The majority of stinging insects in the United States are from bees, yellow jackets, hornets, wasps, and fire ants. Severity of reactions to stings varies greatly. Avoidance and prompt treatment are essential. In selected cases, allergy injection therapy is highly effective.
Sinus Infection vs. Allergies
Both sinus infections and allergies (allergic rhinitis) cause symptoms such as runny or stuffy nose and fatigue. Sinus infection (known as sinusitis) is inflammation of the sinuses, caused by infection from bacteria, viruses, and/or fungi (molds). Allergic rhinitis occurs when certain allergies cause nasal symptoms. When a person with allergies breathes in an allergen, such as pollen, dust, or animal dander, symptoms such as runny or stuffy nose, itching, sneezing, and fatigue occur.
Drug Allergy (Medication Allergy)
Drug or medication allergies are caused when the immune system mistakenly creates an immune response to a medication. Symptoms of a drug allergic reaction include hives, rash, itchy skin or eyes, dizziness, nausea, diarrhea, fainting, and anxiety. The most common drugs that people are allergic to include penicillins and penicillin type drugs, sulfa drugs, insulin, and iodine. Treatment may involve antihistamines or corticosteroids. An EpiPen may be used for life-threatening anaphylactic symptoms.
COVID-19 vs. Allergies
Though there is some overlap in allergy and COVID-19 signs and symptoms there are also significant differences. Symptoms that they have in common include headache, fatigue, tiredness, shortness of breath, wheezing, and sore throat. Fever does not occur with allergies but is one of the defining symptoms of COVID-19 infections.
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Medications & Supplements
Report Problems to the Food and Drug Administration
You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.
Professional side effects and drug interactions sections courtesy of the U.S. Food and Drug Administration.