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A member asked:

How long after a reaction does it take for anaphylaxis to start?

A doctor has provided 1 answer
Dr. Michael Zacharisen answered

Specializes in Allergy and Immunology

Minutes to hours: The most severe anaphylactic reactions tend to occur sooner and it may only by a couple of minutes. Less severe systemic allergic reactions (but still considered anaphylaxis) may occur several hours after the allergen exposure.

Dr Jacobs agreed

Answered 5/8/2018

4.1k views

Thank

Related Questions

A member asked:

I have to take amoxicillin but Im scared im allergic all of a sudden. ive had amoxicillin many times before and never had any allergic reaction to my knowledge. would I experience anaphylaxis after taking one pill/dose? Or just rash the first time?

6 doctors weighed in across 2 answers

A member asked:

If you take an antihistamine before you ate such as Zyrtec, would that help prevent a severe allergic reaction such as anaphylaxis?

A doctor has provided 1 answer

A member asked:

How long does a anaphylaxis reaction take to happen usually? Im taking augmentin (amoxicillin and clavulanate) for the first time and i freak out about stuff like that.

A doctor has provided 1 answer

A member asked:

I have an extreme anaphylaxis reaction to amoxicillin and augmentin, my doctor just prescribed me cefdinir. Is it safe to take? If I do begin to have

A doctor has provided 1 answer

A member asked:

My doctor said that if moxifloxacin 400mg taken once a day for 10 days doesn't help my sinus infection. Then he will prescribe Cefdinir. I have a history of severe allergic reaction including anaphylaxis to penicillin. Is it safe to take cefdinir?

A doctor has provided 1 answer

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How much time does it take for anaphylaxis to kick in after a reaction?
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