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A member asked:

How long do allergy tablets such as loratidine and cetirizine last? if taken before bed is it still affective throughout the next day?

A doctor has provided 1 answer
Dr. John Chiu answered

It is supposed to: last 24 hrs but some may need to take it more frequently.

Dr Robinson and another doctor agreed

Answered 1/28/2015

3.3k views

Thank

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