*ZYRTEC® 10 mg starts working at hour 1 and Claritin® starts working at hour 3, based on first dose on the first day of a 2-day study in 2 pollen- chamber studies. Primary endpoint measured mean improvement from baseline in Major Symptom Complex (MSC) severity score. MSC symptoms included runny nose, sniffles, itchy nose, nose blows, sneezes, and watery eyes.
References:
1. Data on file. Johnson & Johnson Consumer Inc., McNeil Consumer Health Division.
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