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how long for allegra to work

A 32-year-old member asked:
Dr. Brant Ward
13 years experience Allergy and Immunology
20-30 minutes: Oral antihistamines like Allegra (fexofenadine) need to be absorbed by the digestive system and distributed thru the body before they are effective--a ... Read More
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Dr. Heidi Fowler
25 years experience Psychiatry
Allegra: Allegra usually starts working within an hour.

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A 48-year-old member asked:
Dr. Andrew Murphy
29 years experience Allergy and Immunology
Pretty Quickly: Allegra (fexofenadine) and most otc antihistamines has its effect within the first 30 -60 minutes.
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A 35-year-old member asked:
Dr. Andrew Murphy
29 years experience Allergy and Immunology
Hours: Allegra (fexofenadine) and most oral antihistamines will start to work within an hour or so. It does not take days for these medications to work.
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Dr. Heidi Fowler
25 years experience Psychiatry
Allegra: Allegra can start working within a hour.
A 47-year-old member asked:
Dr. Jeffrey Rumbyrt
32 years experience Allergy and Immunology
Read the label: There is considerable debate about the accuracy of label expiration dates. However, as a general rule, it is best to adhere to what the label states ... Read More
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A 41-year-old member asked:
Dr. Michael P Vaughn
34 years experience Allergy and Immunology
Antihistamines: The antihistamines Allegra (fexofenadine), Claritin (loratadine), and zyrtec (cetirizine) can last in your body for more than a week. Most allergists ... Read More
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A 26-year-old female asked:
Dr. Tiffanie Noonan
20 years experience Pediatrics
About an hour...: Allegra is an "as needed" allergy medication so it's effect is not dependent of taking every day - of course for many people "as needed" IS daily. Yo ... Read More
A member asked:
Dr. Susan Rhoads
38 years experience Family Medicine
Your age?: We need to know your age. Please put it in your public profile. We cannot answer questions from minors. Knowing your country or state helps, too. Age ... Read More
A 36-year-old member asked:
Dr. Michael Zacharisen
33 years experience Allergy and Immunology
Allergy, yes: Allegra (fexofenadine) is an antihistamine that could help treat hives triggered by insect stings, but will likely have less effect on bug bites in my ... Read More
A 43-year-old member asked:
Dr. Michael P Vaughn
34 years experience Allergy and Immunology
Decongestants: In the combination drugs like claritin-d, Allegra-D or zyrtec-d the decongestant medication is formulated for slow release over a period of 12 (clarit ... Read More
A 34-year-old female asked:
Dr. Al Hegab
Dr. Al Hegab answered
40 years experience Allergy and Immunology
Yes: You can for a day or two, depending on why you need it for, if longer you need a doctor to look at you, you might need additional/different medicine, ... Read More

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